When I try to uninstall a program from Windows 7 through the Control Panel (Control Panel\All Control Panel Items\Programs and Features, and not a third-party software like Revo Uninstaller) I see this error message:
Please wait until the current program is finished uninstalling or being changed
How can I know which program is being installed or uninstalled?
Looking at the task manager can give some hints:
but it's a bit tedious and might not be obvious. Is there a better way? And without having to just restart Windows?
Several people use the same computer (using the same Windows account). Taskbar doesn't always show all programs as some being installed or uninstalled might not have a taskbar item (typically a background process that is on hold for whatever reason).
Do yourself a favor and restart the computer.
By doing so, windows will tell you which programs are still in use. After it restarts, try to uninstall the same program you did before, it should most likely work again.
If you are not the only person on the computer, its impossible to know what the other users have done while you were not there, If there are no programs running actively, it sounds like some kind of weird glitch I've never heard of.