Bug causing blank window

  achilles123 11:28 22 Jul 04

After I leave my PC unattended for around 50 minutes a blank window appears on the desktop, about 400 x 300 pixels with a button "CLOSE" at the bottom of it. The PC won't respond to ctrl-alt-del, so I can't find the source. If I click on the button it goes away, but having done what? AdAware, spybot, and Norton antivirus, all latest updates, can't find anything. The system is win 98se, 128 meg, with spybot resident, Norton Internet Security, Mozilla and my ISP's dialler in the system tray.
Any suggestions welcome

This thread is now locked and can not be replied to.

Nintendo Switch review: Hands-on with the intuitive modular console and its disappointing games…

1995-2015: How technology has changed the world in 20 years

This abstract video touches on division in our technologic world

Best alternatives to iTunes for Mac | Best music players for macOS: Free your music from the…