If you find that the escape key is no longer responding (or only intermittently) in AutoCAD, check whether you have an instance of Photoshop or Photoshop Elements open, as this program seems to commandeer the escape key even when it is not the window in focus.
We’ve had an odd one today: Before installing a copy of Photoshop Elements 6 on a Vista machine, we thought it best to uninstall an older version 2 that was on the system in case anything got fouled up by the new version (or rather the old version fouled up the new install).
That was easier said than done. There is no uninstall option under Program files, so Control Panel was used, but it threw back the error that the “‘Uninst.isu’ file is not valid”. Reinstalling version 2 in an attempt to fix any corruption was also not successful, but we then noticed that the uninst.isu filedate had not changed.
After trashing the file, we again reinstalled v2 and uninstall then worked OK.