I'm replacing an older Windows Server 2012 R2 Remote Desktop Services server with a new Windows Server 2019 system. In 2018, we purchased 35 Windows Server 2019 Remote Desktop Services CALs through an Open license agreement. The CALs were used with the old setup, and I'm now trying to activate or install them on the new 2019 license server.
The new server reports that the licenses aren't valid and asks me to use another activation method. Phone activation no longer works because the listed numbers appear to be unavailable. The web-based process seems to complete, but the final step leaves the pack ID blank.
The license listing is similar to: "WIN RMT DSKTP SVCS CAL 2019 SNGL OL," quantity 35. Do I need to migrate the CALs from the old license server, use different agreement details during activation, or contact licensing support? I'd prefer to avoid purchasing another license pack if these CALs can be transferred.
3 Answers
Activating the license server and installing the CAL pack are separate steps. In Remote Desktop Licensing Manager, first confirm that the new 2019 license server itself is shown as activated. Then install the CALs. For Open licenses, the wizard may require the agreement or license information from the licensing portal rather than a product key. Depending on the agreement type, you may need to choose “Open License” or “Other Agreement” and enter the corresponding agreement and authorization numbers.
The CALs may already be associated with the old Remote Desktop license server. In that case, use the official RDS CAL migration process to move them to the new server. Don’t decommission the old licensing server until the new one shows the CAL pack as installed. If the licenses need to be released by the licensing clearinghouse, you may have to open a support case so Microsoft can handle the transfer.
I hadn’t considered that the CALs might already be tied to the old server. I’ll try the migration process before removing the 2012 R2 system.
First verify that the CALs are actually for Windows Server 2019, since older 2012 R2 CALs generally won’t cover a 2019 deployment. Based on the product description you provided, though, these appear to be 2019 CALs, so the version itself may not be the issue.

The empty pack ID could indicate that the agreement details were entered in the wrong fields or that the selected licensing program doesn’t match the purchase type.