Ran PdnRepair.exe, gave this output:
The return code from this utility is 0 (success), 1 (fail), or an MSI error code like ERROR_SUCCESS_REBOOT_REQUIRED (3010).
Use /nopause to avoid 'Press Enter to exit...' at completion.
* Opening registry key, HKEY_LOCAL_MACHINE\SOFTWARE\paint.net: ok
* Retrieving MSI product code GUID from ProductCode value: {6FED3D93-C0FA-4BD7-A36F-7FC53698244F}
* Attempting to repair with MsiReinstallProductW(REINSTALLMODE_FILEREPLACE) (same as msiexec.exe /fa): success, but REBOOT IS REQUIRED, dwResult=3010
Return code is 3010
Press Enter to exit...
I'm restarting my computer now.