Windows deselected for no reason

This problem has been plaguing me for a while now, but I have still found no solution. I decided to come here to see if anyone else can help me out.

Basically, what seems to be happening is when I'm using a program or something, like, for example, Google Chrome, the window will randomly be deselected or deactivated. It's like someone clicked on another window. Normally, this isn't a huge deal. I just click on the window and keep typing until it happens again (it usually happens two or three times then stops for a while); It's just annoying. But the real issue is when I'm playing a full-screen game, where it's constantly minimized. Not only does it take a good minute or two for my slow computer to pull the window back up, but this also sometimes crashes games, like Team Fortress 2. Thanks to this... thing, I haven't been able to play any games for a while.

Any help would be great. If you need any more information, I'm glad to give it to you. I've considered re-installing Windows just to get this taken care of.

I wonder if it's some hotkey combo you're accidentally hitting that changes window focus. That's about all I can think of other than some unruly program running in the background that keep grabbing the focus.

Download, install, update and run a Full Scan with Malwarebytes.

Next run SFC -SCANNOW Command.

Is this a clean install, factory preinstall, or in-place Upgrade of Vista? Did you get a Win7 INstallation DVD with your computer?

I've been having this same problem and it started shortly after a fresh install, which was quite disappointing. I've suspected malware from the start but I've just been too lazy to do anything about it since most of the time I play games in windowed mode so I can multi task without minimizing my game. I don't run anti-virus software because it tends to slow my PC more than a virus would and I keep things backed up if I need to reinstall. But after reading this thread, I decided to give Malwarebytes a try. I really like that it doesn't run all the time, only when YOU tell it to do something. That's one of my biggest gripes with most programs out there, they just scan stuff and warn you about things that aren't even a real threat (no CD cracks, etc.) whenever they feel like it. Anyway, Malwarebytes found 6 infected files and 3 infected keys in less than 5 minutes and deleted them all successfully. None of the files were directly related to my games (although I admit still may have come from a selected few games, I'll check after running them again). I scanned again after rebooting and 0 infections were found. I think I'm gonna keep this program. Thanks for the suggestion, gregrocker!!! I'll report back if any windows get deselected again.

Try installing free lightweight MS Security Essentials or Avast 6 to run with the Win7 Firewall, which needs to be kept updated as first line of defense.

These AV's are light enough they shouldn't slow you down at all, or if they do you'd really only need 2gb of RAM to get above them, an easy and inexpensive upgrade which will make your games run faster too.

I think I will give those a shot. When I first adopted my theory of not using this type of software 4 years ago, my PC wasn't near as powerful as it is today.

Old:
-1.8Ghz Core 2 Duo
-3 GB DDR 2 533 MHz RAM
-nVidia 7300GS video card
-320GB HDD

New:
-3.2 GHz x6 AMD Phenom II
-8 GB DDR 3 1600 MHz RAM
-nVidia GTX 470 x2 in SLI
-1 TB HDD + 1 TB External HDD (100 GB partition on internal HDD for the OS to make it easier to reinstall if needed)

I suppose it's time to start keeping my OS safe.