TurboTax 2013 on Windows 7 32-bit. This is 100% reproducible.
I launch TurboTax and immediately check for updates. If updates are available, I click "OK" to start the update. If multiple updates are available, all of them install successfully, except for the "program" update. If fails, because the installer has no permission to access C:\Windows\Installer\{2A4EEB5C-something-or-other}.
No kidding. I am unable to delete that folder, using all the Windows tricks I know.
I reboot Windows 7. The bad folder is gone! I repeat the update process. This time, only one update is available, the "program" update. Installation is successful.
This is annoying and inconvenient. Intuit publishes many of these updates during tax season. Anyone have a solution?