I have encountered the same situation 3 times when uninstalling and reinstalling FSX.
- Firstly, please make sure you have no option anymore to uninstall FSX via Add/Remove Programs in the Control Panel
- Secondly, follow the guides to clean up the leftovers on your hard disk, as described in the guides on Avsim/PMDG
- Thirdly, in the past you would have run the "Windows Installer Cleanup Utility". However, Microsoft abandoned this tool some years ago and now they have a FixIt called " Program Install and Uninstall troubleshooter "
you can find it here:
http://support.microsoft.com/kb/290301/en
the downloaded file will be:
MicrosoftFixit.ProgramInstallUninstall.MATSKB.Run.exe
It basicly has the same goal as the older version, but now it's more up to standard with their latest OS'es.
- So download the FixIt
- Run the FixIt
- Choose that you have problems UNinstalling a program
- The tool will look in the registry for "installed programs" and you will see Microsoft Flight Simulator X listed in the overview.
- Select it, and instruct the tool to clean up the mess that FSX's installer left behind.
A reboot might be adviced after this, and you should be able to install FSX again.