Switch from Legacy BIOS to UEFI on existing installs of Windows Server 2016 (and 2012 / 2012 R2)

With most modern servers now shipping with UEFI enabled by default and many virtual hypervisor platforms supporting it for guest VMs as well, you may wish to switch your existing installations of Windows Server 2012, 2012 R2 or 2016 from booting with legacy BIOS to booting with UEFI. Thanks to a small tool introduced by Microsoft in Windows 10 1703, MBR2GPT.EXE, this can be done very easily.

You will need to download a copy of Windows 10 1703 or later in order to follow this guide as you need a copy of MBR2GPT.EXE and you need to boot your server into the version of WinPE that comes with these releases of Windows 10. You cannot run the tool in versions of Windows prior to 1703 (which, technically, Window Server 2016 is as it uses the same codebase Windows 10 1607).

Make certain your platform supports UEFI booting before continuing with this guide. If it does not, you will no longer be able to boot into Windows after you have changed the partition table from MBR to GPT.

If this process fails it has the potential to make your server unbootable, corrupt your data and cause lengthy downtime. Make certain you have an adequate backup of your server and a restoration process in place before proceeding.

Okay, with the big scary warnings out of the way, let’s get going!

First start by loading the Window 10 1703 (or later) ISO onto a USB drive, DVD, or if you’re following this process on a VM, mount it directly on the VM. Restart your server and boot the server from the Windows installation media. Click Next on the language selection screen and on the next screen click Repair your computer.

When the options screen comes up select Troubleshoot, and in Advanced Options select Command Prompt. You’ll find yourself at the command prompt in X:\Sources. Change directory to X:\Windows\system32 and start diskpart. Type list disk to list the disks attached to the system and note down the one that contains the OS. This will likely to be disk 0 but may not be depending on your servers’ disk layout.

diskpart List Disk

Exit diskpart and type MBR2GPT.exe /validate /disk:0. This will run the MBR2GPT tool on your OS disk to validate that it is ready for the conversion. If it is successful, run MBR2GPT.exe /convert /disk:0 and wait for the conversion to complete – it should not take long.

MBR2GPT Convert

That’s it for the conversion. Now restart your server, enter setup and enable UEFI booting. Save and exit and Windows should boot right up without any issues.

Now there is some optional clean up you can do. How optional it is depends on if you’ll ever want to extend the size of the drive. On a physical server it is unlikely your partition doesn’t already use the full size of the drive, however on a VM where it is possible to increase the size of the disk, you may have need to extend it in the future. It also depends on if you use BitLocker or not – more on that in a moment.

Here’s the deal. In Windows, open a command prompt and start diskpart. Type select disk 0 and then list partition. You will see three partitions – a 500 MB recovery partition, your OS partition and a 100 MB EFI system partition. That 500 MB partition is no longer in use since you no longer have an MBR partition. The new system partition is that 100 MB one at the end, and because it is at the end it will block you extending your OS partition. Fortunately, you can reuse that 500 MB of space and put the EFI system partition there instead.

If you use BitLocker to encrypt your drive the 500 MB partition also contains the unencrypted system files needed to start your computer. In this case, you cannot delete the partition. If you really need to be able to extend your partition in the future you can either unencrypt your drive, move the partition and then re-encrypt it, or use a third-party partitioning tool to move the EFI system partition to the front of the disk.

If you want to complete the partition clean up, here’s what to do. First, reboot the server and use the same steps as earlier with your Windows 10 installation media to end up back at the command prompt. From here, enter diskpart and type select disk 0 and then list partition. Note down which partitions are the 500 MB recovery partition and 100 MB system partition (typically these will be partition 1 and partition 3). Proceed to delete these partitions by first selecting them and then deleting them, using the commands select partition 1 followed by delete partition override and then select partition 3 followed by delete partition override.

diskpart Delete Partitions

Now create a new EFI system partition at the front of the disk using the command create partition efi size=100, format it using format quick fs=fat32 and assign it a drive letter using assign letter=s. Next, use the list volume command to get a list of volumes and make a note of the drive letter your OS drive is on (very likely C).

diskpartListVolume

Exit diskpart and type bcdboot C:\Windows /s S: to copy the necessary system files to the new EFI system partition.

Finally, enter diskpart one last time, type select disk 0 and then select partition 2 and then type extend to reclaim that 100 MB of space at the end of the drive (may as well, right?) This will leave you with 2 partitions – the 100 MB EFI system partition at the beginning of the drive and your OS partition. Exit diskpart and restart your server.

diskpartExtendPartition

And that’s it, the server now boots with UEFI and the partitions are all tidied up1.

1The astute among you will have realised that actually, the partitions aren’t quite as clean as you might like. Due to the old system partition being 500 MB and the new one being 100 MB, there is now 400 MB of unused space between the system partition and the OS partition. You have a few options here. The first, and simplest, is to actually create the new EFI partition with 500 MB of space rather than 100 MB. It doesn’t need that much space, but it will look better in Disk Management not having that random unused space between the partitions. Your second option is to simply leave it there, which could be beneficial in the future. If you ever turn on BitLocker it will need to create a 350 MB partition to store the unencrypted system files needed to boot your computer, and it can do so inside that 400 MB of space. Your third option is to use a third-party partitioning tool which is capable of extending your OS partition into the space in front of it, which is something that diskpart cannot do.

Migrating your Microsoft PKI infrastructure to Windows Server 2016 (Part 2)

Migrating your Microsoft PKI infrastructure to Windows Server 2016 (Part 1)
Migrating your Microsoft PKI infrastructure to Windows Server 2016 (Part 2)

In the second part of this guide I will be migrating my online issuing CA to Windows Server 2016. As before this guide is written as a guide to upgrade from a Windows Server 2012 R2 CA to a Windows Server 2016 CA, however it is equally valid for moving a CA from any older version of Windows server to Windows Server 2016.

The majority of the steps in this guide are identical to the steps for the offline root CA, however there are a few differences as this is a domain joined system and at the end of the guide you will need to re-register any certificate templates you have.

Preparation

Start by building your new Windows Server 2016 server. I recommend again that you give it the same name as your current issuing CA, although it is possible to change it if you are willing to modify some registry keys later on in the process. If you do give this server the same name do not join it to the domain yet. This will be done later in the guide once the existing issuing CA has been removed from the domain. You should also patch the new server with the latest Microsoft patches at this time.

Migration – Backing up your existing issuing CA server

The first step is to back up the CA using the command certutil -backup C:\SubCABackup KeepLog. If you do not care about keeping the logs then you can omit the KeepLog part and instead the logs will be truncated.

You will need to enter a password, remember it and make it complex as this backup contains your issuing CA private key.

backupIssuingCA

The next thing to backup is the CA configuration, which is stored in the registry in the following location: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\CertSvc. Back it up by typing reg export "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\CertSvc" C:\SubCABackup\CertSvcRegBackup.reg

backupIssuingCAReg

You now also need to make a record of what certificate templates you have created as these will need to be re-registered on the new CA. The easiest way to do this is to run the command Certutil -catemplates > "C:\SubCABackup\Catemplates.txt". This pipes the output to a file called Catemplates.txt which you can open later to see the names of the templates.

It is also worth backing up your CAPolicy.inf file which you can do easily enough by copying it into the backup folder by typing copy C:\Windows\CAPolicy.inf C:\SubCABackup.

Once you have done the work to backup your existing issuing CA it is time to uninstall the CA role. Before doing this run Get-WindowsFeature in Powershell and have a look at what additional CA features you currently have installed (for example you may have the Web Enrolment service and/or Online Responder roles installed). Make a note of these so that you know what features to install on the new issuing CA server.

windowsFeatures

To uninstall the certificate authority role use the Powershell command Remove-WindowsFeature Adcs-Cert-Authority and press enter. If you did have any additional CA roles installed you may need to remove those first; in my case I had to remove the Web Enrollment service (this was done by running Uninstall-AdcsWebEnrollment).

You will need to restart the server to complete the role uninstall.

It is now important that you copy the SubCABackup folder to your new issuing CA as the next step is to remove the existing issuing CA from the domain and power it down.

To remove the old issuing CA from the domain using Powershell type Remove-Computer HOSTNAME replacing HOSTNAME with the name of your issuing CA. Restart the server to complete the domain removal and then power down the old issuing CA.

Load Active Directory Users and Computer from a management workstation and delete the computer account for the old issuing CA.

Migration – Configuring your new issuing CA and restoring from the backup

Power on your new issuing CA and join it to the domain. You can do this from Powershell by typing in Add-Computer –DomainName yourdomain.com -Credential YOURDOMAIN\Administrator replacing the domain with your domain and the admin account with your admin account. Restart the server to complete the domain join.

Once the reboot has completed you must install the CA role. Do this using Powershell by typing in Add-WindowsFeature ADCS-Cert-Authority and pressing enter. As with the root CA this now needs to be configured using the backup from the old issuing CA, which you do with the following Powershell command:

Install-AdcsCertificationAuthority -CAType EnterpriseSubordinateCA -CertFile "C:\SubCABackup\LaptopPoc Sub CA.p12" -CertFilePassword (Read-Host "Enter password" -AsSecureString)

Replace the value after -CertFile with the path and name of the .p12 file from your issuing CA backup. When you press enter you will be prompted for the password you used to back up your original issuing CA.

If this step is successful you will receive ErrorID 0 as your return code.

Next you need to restore the database and logs. Before you do this the CA service must be stopped. Do that by typing in net stop certsvc and pressing enter. Once it has stopped restore the database and logs using the command certutil -f -restore C:\SubCABackup. The -f forces an overwrite of the data that was configured in the barebones CA setup. Once again you must enter the password you used to backup your original issuing CA.

Before starting the CA service you must import the registry configuration. If you opted to change the name of your issuing CA server you need to go through the C:\SubCABackup\CertSvcRegBackup.reg file and replace and reference to the old server name with your new server name. Once this is done you can import the configuration by typing reg import "C:\SubCABackup\CertSvcRegBackup.reg".

Finish up the restoration process by copying the CAPolicy.inf file back into the Windows directory by using the command copy C:\SubCABackup\CAPolicy.inf C:\Windows

One final thing

There may be one other thing you need to consider before you can start your new issuing CA and that is the location of the web CRL. This is a website that is likely hosted inside your network that contains an up to date certificate revocation list which your issuing CA needs to have access to before it will start. This may not be a problem for you at all if your web CRL is hosted on an separate web server that you did not touch during this migration. However, if like me your web CRL is hosted on your issuing CA, this will have been lost when you decommissioned your previous issuing CA.

To resolve this you will need to install IIS on your new issuing CA and configure a new site to host your CRL. The URL to the CRL must match the previously configured CRL location, so if it used to be accessible via http://PKI.yourdomain.com then it must still be accessible there now. You can find the URL for your CRL by looking at any certificate issued by your CA, going to the Details pane and looking at the CRL Distribution Points field.

Restoring your certificate templates

With everything else done you can now start your new issuing CA by typing in net start certsrv. Now you will need to re-register each of the certificate templates you had on your previous issuing CA. Open the Catemplates.txt file you saved by typing notepad Catemplates.txt and use it as a reference for the names for each of your templates. You will need to run the following command for each one:

certutil -setcatemplates +TEMPLATENAME

Replace TEMPLATENAME with the name of your certificate template. Note that + before the template name.

restoreCATemplates

Do this for each of your templates. Once completed all of your templates will be available again and all issuing permissions will be retained.

That completes the process of migrating your issuing CA to a new server. If you have multiple issuing CA servers you will need to repeat this process for each of them. You may also need to reinstall any additional certificate service roles such as Web Enrollment1, which you can do either in Powershell or by using a management workstation with Server Manager. You should make sure you delete the C:\SubCABackup folder so that you don’t leave your issuing CA private key laying around.

1You may encounter error 0x80070057 when reinstalling the Web Enrollment role. If you do, take a look at this blog post: AD: Certification Authority Web Enrollment Configuration Failed 0x80070057 (WIN32: 87)

Migrating your Microsoft PKI infrastructure to Windows Server 2016 (Part 1)

Migrating your Microsoft PKI infrastructure to Windows Server 2016 (Part 1)
Migrating your Microsoft PKI infrastructure to Windows Server 2016 (Part 2)

As part of my efforts to upgrade my POC lab to Windows Server 2016 I got around to migrating my PKI infrastructure. This consists of an offline root CA and an online issuing CA. In Part 1 of this guide I will be migrating my offline root CA to Windows Server 2016.

This guide is written as a guide to upgrade from a Windows Server 2012 R2 CA to a Windows Server 2016 CA, however very little has changed since the Windows Server 2003 days and this guide is equally valid for moving a CA from any older version of Windows server to Windows Server 2016.

I am a big advocate of the core versions of Windows Server and in this guide I will be migrating from and to Windows Server core. A CA is a perfect example of a server that does not need the overhead of the GUI and additional services that comes with the full GUI edition of Windows Server and if you don’t already use core for your CA, this is a perfect opportunity to migrate to one!

Preparation

In preparation for the migration build your new Windows Server 2016 server. I recommend that you give it the same name as your current root CA server – it is possible to give it a different name however this will require changing registry keys later on in the migration process. Take this opportunity to patch it with the latest Microsoft patches!

Migration – Backing up your existing root CA server

The first step is to back up the CA using the command certutil -backup C:\RootCABackup KeepLog. Note that the KeepLog part is optional, however without it the backup will truncate the logs. I prefer to bring the whole lot across in case the logs are ever needed in the future for auditing purposes.

You will need to enter a password, remember it and make it complex. This backup contains your root CA private key, do not make it easy for an attacker to obtain.

certutilBackup

The next thing to backup is the CA configuration, which is stored in the registry in the following location: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\CertSvc. Back it up by typing reg export "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\CertSvc" C:\RootCABackup\CertSvcRegBackup.reg

regBackup

Additionally it is worth backing up your CAPolicy.inf file which you can do easily enough by copying it into the backup folder, by typing copy C:\Windows\CAPolicy.inf C:\RootCABackup

copyPolicy

Finally, copy the RootCABackup folder to your new CA.

Migration – Configuring your new root CA and restoring from the backup

Log on to your new root CA server and start by installing the CA role. The easiest way to do this is with PowerShell, so type powershell into your administrative CMD prompt and enter the following command to install the CA role: Add-WindowsFeature ADCS-Cert-Authority

Now configure this new CA using the backup of the old CA. This can also be done with PowerShell using the following command:

Install-AdcsCertificationAuthority -CAType StandaloneRootCA -CertFile "C:\RootCABackup\LaptopPoc Root CA.p12" -CertFilePassword (Read-Host "Enter password" -AsSecureString)

Replace the value after -CertFile with the path and name of the .p12 file from your root CA backup. When you press enter you will be prompted for the password you used to back up your original root CA.

If this step is successful you will receive ErrorID 0 as your return code.

configureCA

This restores the root CA private key, however next you need to restore the database and logs. Before you do this the CA service must be stopped. Do that by typing in net stop certsvc and pressing enter. Once it has stopped restore the database and logs using the command certutil -f -restore C:\RootCABackup. The -f forces an overwrite of the data that was configured in the barebones CA setup. Once again you must enter the password you used to backup your original root CA.

certutilRestore

Do not start the certificate authority service just yet! Before doing that the registry settings from the previous root CA need to be restored. Do this by typing reg import "C:\RootCABackup\CertSvcRegBackup.reg"

Note: If you chose to change the name of your root CA server you will need to go through the values in this registry file and change any reference to the old server name to your new server name before importing it.

Finally copy the CAPolicy.inf file back into the Windows directory by using the command copy C:\RootCABackup\CAPolicy.inf C:\Windows

Now you can start the root CA by typing net start certsrv. The service should start with out any issues. To verify this you should log on to a management workstation and load the Certificate Authority MMC snap-in, connect to the new server and verify that your issued / revoked certificates are listed (as this is a root CA there should be very few issued certificates!)

Once you are satisfied that the new server is configured correctly and working, make sure that you delete the C:\RootCABackup folder. As previously mentioned, this contains your root CA private key, you do not want to leave that laying around!

Coming soon is Part 2, which will focus on migrating the issuing certificate authority. Thankfully the steps for this are very similar with only small differences due to it being a domain joined server.

Error 80070057 when attempting to update Windows Server 2012 R2

Once when I was updating some servers running the version of Windows Server 2012 R2 I encountered something odd; no patches appeared in Software Center or in the Windows Update panel, even though the server was several years out of date and definitely had applicable updates!

In WindowsUpdate.log I found the following error message repeating:

cidimage001

The fix for this is to manually download and install KB2919355, which is the April 2014 update rollup for Windows Server 2012 R2. After this has been installed and the server has restarted, re-run your updates scan and updates will show up in Windows Update or Software Center.

Increasing the maximum run time for Windows 10 and Windows Server 2016 cumulative updates

One of the things I have noticed since starting to deploy Windows Server 2016 is that the cumulative updates can fail to install when deployed from SCCM. It starts to run but then times out due to the maximum run time having been reached. By default this is set to 10 minutes. However due to the updates being larger and taking longer to install than updates prior to the cumulative updates era 10 minutes doesn’t seem to be long enough. The fix for this is to simply increase the maximum run time for cumulative updates for both Windows Server 2016 and Windows 10 from 10 minutes to 30 minutes.

Screen Shot 2017-06-05 at 23.12.35

Screen Shot 2017-06-05 at 23.12.47

This is a bit tedious as you’ll have to do it every month for both Windows Server 2016 and every version of Windows 10 you have in your environment. Hopefully Microsoft soon catches on to this and changes the default run time to 30 minutes so that this ceases to be an issue. There is already a Configuration Manager UserVoice entry for this idea, so if you’re reading this, pop over and vote to increase its visibility!

ISATAP failing with error 0x490

ISATAP can be very useful if you need to manage out from a machine with an IPv4 address to a machine with an IPv6 address. This is commonly used where DirectAccess has been deployed as all DA clients will be using IPv6. Being able to RDP to them or use the SCCM Remote Control feature from a machine inside your network is very helpful for the IT support staff – it’s as if the user was just working from their desk like usual!

One time I was configuring an ISATAP interface on a server and I got the follow error in the event log:

Unable to update the IP address on ISATAP.yourdomain.com. Update type: 1. Error Code: 0x490

I scratched my head over this for quite a while – setting up an ISATAP interface should be easy! After a while I remembered that there was a history of disabling the IPv6 components on servers via GPO. It turns out that even though the GPO had been removed, the setting to disable IPv6 had been tattooed on the servers it had once been applied to.

To check this I had a look in the following location in the registry:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\TCPIP6\Parameters\DisabledComponents

The value was set to 0xFFFFFFFF (it may instead be set to 0xFF). This disables enough of the IPv6 components to prevent an ISATAP interface from being able to be created.

Simply delete the DisabledComponents key and restart the server. So long as everything else is set up correctly you will have your ISATAP interface when you next log in.

Scan failed with error 0x80244021 with WinHTTP proxy configured

While trying to update one particular server using SCCM 2012 R2 I discovered that it was not updating, with the following error was appearing in WindowsUpdate.log and UpdatesHandler.log:

Scan failed with error = 0x80244021

In my case this issue was occurring because a proxy server was configured but no exception was in place for the WSUS / SCCM server. This meant that the server was trying to access the WSUS server through the proxy! To see what my proxy settings were I opened an elevated CMD prompt and entered the following command:

netsh winhttp show proxy

The following information was returned:

Proxy Server(s): ProxyServer.local
Bypass List :

As you can see, the bypass list is empty. In order to create an exception for the WSUS server, enter the following command:

netsh winhttp set proxy ProxyServer.local "https://WSUSServer.local" 1, 2

This sets the proxy and sets the WSUS server as an exception. Re-running netsh winhttp show proxy will now show you the following output:

Proxy Server(s): ProxyServer.local
Bypass List : https://WSUSServer.local

As you can see the WSUS server is now part of the bypass list, meaning that attempts to access this website will not go through the proxy.

Restart the WindowsUpdate service and re-run the Windows Update scan. You should no longer see scan error 0x80244021.

1Whether you use HTTP or HTTPS for your WSUS server depends on your WSUS or SCCM configuration.

2If you need to add multiple exceptions enter the first one, followed by a comma, followed by the next one and so on.