While attempting to uninstall a DLP agent an error is presented by Windows:
The cached MSI file 'C:\Windows\Installer\xxxxxx.msi' is missing.
Some maintenance task such as a disk cleanup procedure has removed the original cached msi file from the "C:\Windows\Installer\*" directory.
Using the original MSI that installed the agent can be used to bypass the missing cached msi file
Example command line:
msiexec /x AgentInstall-x64_16.1.msi
Microsoft has published this article as a way to recover missing cached install files:
Restore the missing Windows Installer cache files