A - Partially Deleted Previous Installation Was Detected

If available, restore to a date before the problematic installation or partial uninstall.

Microsoft provides a free tool called (formerly msicuu2, now integrated into the SetupDiagnostic tool). a partially deleted previous installation was detected

Search for "Microsoft Program Install and Uninstall troubleshooter." If available, restore to a date before the

"Partially deleted" can sometimes be a permission error. If the installer cannot overwrite a leftover file in a protected system folder (like Program Files ), it might misinterpret the error as a corrupted installation. Right-click the installer and select to give it full permissions to sweep away old debris. If the installer cannot overwrite a leftover file

It sounds cliché, but a restart clears temporary caches and locks on files. If the previous installation crashed, a background process might still be running, "holding" onto the folder and preventing the new installer from writing to it. A restart kills these zombie processes.