If you want to upgrade your domain controller and make this ready for server 2019. In this case I have only one Domain controller running server 2016.
When you do a Upgrade of your current Domain Controller you may get this message during the Setup of Windows server 2019
Go to the Source files of Windows server 2019 and look for ADPrep
In the command line adprep.exe /forestprep /forest <domainname>
If you press any other key than the C it will quit the upgrade.
Press C
You can see a upgrade from schema 87 to 88
next step is a domain prep
ADPrep /domainprep /domain <domainname>
No reboot is needed, go back to the Setup press refresh and the setup will continue.
Depending on the Computer Speed you will see this
If the installation fails keep an eye on the error code. In this case I had a simulation of this and I skipped some updates.
Checked the code and see the solution.
https://support.microsoft.com/en-us/help/10587/windows-10-get-help-with-upgrade-installation-errors
An error that begins with 0xC1900101 is usually a driver error. If you see any of these error codes, try the following steps first to fix the problem. If these steps don’t work, see Resolve Windows 10 upgrade errors for more detailed technical info.
- 0xC1900101 – 0x20004
- 0xC1900101 – 0x2000c
- 0xC1900101 – 0x20017
- 0xC1900101 – 0x30018
- 0xC1900101 – 0x3000D
- 0xC1900101 – 0x4000D
- 0xC1900101 – 0x40017
- Make sure that your device has enough space. Your device requires at least 16 GB of free space to upgrade a 32-bit OS, or 20 GB for a 64-bit OS. For more info, see Free up drive space in Windows 10.
- Run Windows Update a few times. Download and install any available updates in Windows Update, including software updates, hardware updates, and some third-party drivers. Use the troubleshooter for Windows 10 to fix Windows Update errors.
- Check third-party drivers and download any updates. You can find third-party drivers and installation instructions for any hardware you’ve added to your device on the manufacturer’s website.
- Unplug extra hardware. Remove all external storage devices and drives, docks, and other hardware you might have plugged into your device that isn’t needed for basic functionality.
- Check Device Manager for errors. Select the Start button, then in the search box on the taskbar, type device manager. Choose Device Manager from the results. In the window that pops up, look for any device with a yellow exclamation mark beside it (you may have to select each category to switch to the list of devices). Press and hold (or right-click) the device name and select either Update Driver Software or Uninstall to correct the errors.
- Remove third-party security software. Make sure you know how to reinstall your programs and that any necessary product keys are on hand. Windows Defender will help protect your device in the meantime.
- Repair hard-drive errors. Select the Start button, then in the search box on the taskbar, type command prompt. Choose Command Prompt from the list of results. In the window that pops up, type chkdsk/f C: and press the Enter key. Repairs automatically start on your hard drive, and you’ll be asked to restart your device.
I did do Option 2 and see the updates and installed it and retried the upgrade again and it worked without any issue.
After the update I did a restart for finishing the updates and another restart to make sure everything was fine then I restarted the upgrade successfully,
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informational Artiel about Upgrading Window server And Do you Which are The 10 best hosting Providers in 2019.
Thanks for the informative post. I’m working in a Hyper-V lab running on a W10 Pro computer. Just learning and trying new things. When I try to execute the cmd for adprep, I receive an “Access is denied” error. I’m signed in as the administrator on the DC. Not sure what is happening.
so logon as admin is not say running apps as admin. do right click on the CMD and say run as administrator this will solve your issue
This is an absolutely helpful post. Thank you!
Thanks Chad. Thanks for visiting my blog!
I followed this post and it didn’t work, then I checked the DFL, it was 2003 so I Raised it to 2012 r2, and the problem was solved. Thanks!
good to see that you moved away from the DFL 2003 😉 Thanks for reading my blog
Hello, when I follow these steps I am getting access denied when I run \support\adprep>adprep.exe /forestprep / forest. However I keep getting access denied. I’ve gone through all the permissions and confirmed everything but still getting the error.
Hello
I ran into this problem while upgrading my 2016 servers. I opened the command prompt and ran the \support\adprep>adprep.exe /forestprep /forest but I get access is denied on both machines. I am the admin of the domain and both servers. Not sure why I’m getting this but can’t upgrade until I solve it. Any ideas would be much appreciated.
Thanks
MW
make sure the cmd is in admin mode and you must be a schema admin