Grey rectangle on top left of the screen

I experience sometimes this issue on my Windows 7 laptop: after the Windows GUI has finished booting, a small grey rectangle appears on the top left of the screen.

It stays in front of anything I drag over (Desktop, application windows, etc.), except the mouse pointer which goes in front of the rectangle. Logging out and in again fixes the problem.

On forums around the web people found different causes for this problem: Catalyst Control Center, Razer Synapse, Dell Backup & Restore Manager, and so on. In my case, none of these apply.

Anyone knows whether there is a common cause for this issue?

dr01

Posted 2015-10-11T16:53:00.630

Reputation: 2 509

I had this happen with Internet Explorer 8 about five years ago on embedded WMVs. It would not be there, I'd open a page with a video, the video would play fine, but as soon as I clicked off of the page, the area where the video was turned black and remained there until a reboot. – 287352 – 2015-10-12T06:17:44.503

1I'd bet it's coming from Greenshot. – MicSim – 2015-10-12T10:08:55.130

I've had it happen with Adobe Acrobat. The box wasn't the same shape, but it would happen all the time. Finding was trial and error because Spy++ and Process Explorer didn't help find the window. – JPhi1618 – 2015-10-12T14:18:33.360

@MicSim +1 You'd have won. It was Greenshot indeed; please see my comment on the accepted answer. – dr01 – 2015-11-01T09:43:44.617

Answers

It is probably supposed to be a "hidden" window from a shoddily written application. To figure out which process it belongs to, download Process Explorer, an excellent diagnostic tool from Sysinternals.

Run the program and accept the EULA, no installation required. In the toolbar there is an icon that looks like a target, titled "Find Window's Process." Click and drag from that icon to the gray region. When you release the mouse, Process Explorer will highlight the process that owns the window.

The Description and Company Name columns might help identify the responsible application, or you could just search the Internet for the process name. Double-clicking the row produces additional interesting information.

Ben N

Posted 2015-10-11T16:53:00.630

Reputation: 32 973

1If anyone encounters this type of issue in Linux, assuming X11, you can achieve a similar result using a standard tool to ID the application: open a terminal, run xprop, and click within the offending rectangle. This will work unless the window (deliberately or not) omits all useful X properties. (If - I can't recall - xprop includes a PID, then even better.) – underscore_d – 2015-10-12T15:18:27.933

The issue just happened again today. I followed your advice and the culprit turned out to be Greenshot. Exiting the program made the rectangle disappear. Thanks. – dr01 – 2015-11-01T09:42:27.530