Uninstalling Remote Desktop with MSI Does Not Remove the Mstscax.dll File

If you install Remote Desktop by using Microsoft Installer (MSI), MSI installs the Mstsc.exe, and Mstscax.dll files in the System32 folder, but if you uninstall Remote Desktop by using MSI, you cannot remove the Mstscax.dll file.

To remove the Mstscax.dll file, you have to perform a complete removal of Remote Desktop in Microsoft Management Console (MMC). When you uninstall Remote Desktop this way, you will receive a prompt to confirm that you want to delete this file.

This behavior is by design.

Leaving this file in the System32 folder does not cause any negative effects.