How can I find out which application is stealing focus in Vista?

"Try Sysinternals ProcessExplorer. It's a task manager replacement tool which accurately tracks every tiny little process that pops up.

Leave it running and return to your app. When the problem occurs alt-tab to Procexp and you may be able to catch what is grabbing all the attention.

Edit: I have literally just found this: Auslogics TaskManager Which would almost certainly help you identify what's going on, with a more intuitive interface and a wealth of more easily accessible information than Procexp."

"I used the excellent Adminscope Focus Logger for this problem. The culprit for me was some Epson utility which did nothing useful and ran as a scheduled task.

Just read the instructions and leave the focus logger running for a while to detect the program which takes the focus away. The program runs on XP (and, presumably, other version of Windows, such as Windows 7, 8, etc.).

EDIT: and, unlike some of the programs listed in this thread, it's freeware."

"I used the code at http://archive.msdn.microsoft.com/templeofvb/Release/ProjectReleases.aspx?ReleaseId=18 just now to find it.

For me, it was Google talk, lab edition."

"I had this problem as well, so annoying. I used that Auslogics TaskManager, and found a process on there (forget what it was called) that was some video player for AIM ads. Google unknown processes .exe's until you find it, then uninstall it via the Control Panel.

There was one more thing I saw, and it was this Java automatic running thing, you have to go into: Start button, Control Panel, Java, Advanced Tab, Miscellaneous, and UNCHECK ""Java Quick Starter""

I did those two things, and problem so far seems to be completely solved :). Also, make sure you close AIM and any web browsers before you uninstall."