I have a client who recently migrated from an on-premises Exchange server to Exchange Online, and now the Exchange server we set up a few years back is just sitting unused. They currently have a Remote Desktop Services (RDS) server operating on Windows Server 2008, and I'm considering shutting it down and repurposing the Exchange server as the new RDS. Since we've already migrated all the mailboxes six months ago, the Exchange server mainly holds backups of those old mailboxes and is inactive. I had previously disabled all its Exchange services upon migration and now I'm looking for advice on potential pitfalls or important aspects to address in this transition. My plans include archiving all OST/PST files, uninstalling Exchange, and then setting up the RDS roles with Gateway and licensing while also getting new Client Access Licenses (CALs). I would appreciate any insights to ensure I'm not overlooking anything major. Thanks!
9 Answers
You didn’t mention the OS version of the Exchange server. If it's on 2012 R2, you might want to skip that since it’s at end of life. You’ll need new RDP CALs too, so ensure you get the right ones based on the OS you choose. Just like others have mentioned, a fresh installation is the way to go.
Consider doing a fresh install of the Windows OS on the Exchange server instead of just uninstalling Exchange. This helps avoid any legacy issues that may linger from its previous use. Just to clarify, when you say 'archive,' make sure you're moving the old mailboxes to separate storage and not just placing them in a folder.
A clean slate is always best! After reinstalling the OS, you can go ahead with your plan for the RDS.
Definitely wipe the original OS before proceeding. It’s not advisable to install new services on top of old ones, even if you've uninstalled Exchange. Also, have you looked into virtualizing the RDS? It could really help with disaster recovery and backup options.
Have you considered what apps will be accessed on the RDS? It might be worth exploring if an app proxy could be an alternative solution.
Wipe it all clean and do a fresh install. Virtualizing your workloads can prevent situations like this in the future.
If AD sync is involved, be cautious about uninstalling Exchange. It’s better to reformat the server instead. Uninstalling the last Exchange server can lead to troubles with Active Directory management. It’s crucial to maintain the server for managing attributes until a new setup is in place. Check Microsoft's resources for guidance on this.
Make sure to archive and export the mailboxes first. After that, properly remove the Exchange server from the domain, wipe it, and reinstall a fresh OS for the RDS.
Absolutely! If it’s a physical server, you should wipe everything off it before converting it to an RDS. Starting fresh reduces complications.

I hadn't considered a fresh OS install before. That's a great suggestion, thanks!