"C drive with Avast antivirus"
"I have run a Windows Essentials security scan"
"I scanned the Registry it was squeeky clean"
These are quotes from above. Quoted the above to help troubleshoot your system.
Avast! just recently updated their a/v from version 7.0.1426 to 7.0.1451. Some users at avast forum are reporting memory leaks with symptoms similar to yours, text missing, etc. This memory leak is affecting only some Win 2000 and XP users. Other operating systems are not affected. I am running XP Pro SP3, and it is not affected by this bug.
http://forum.avast.com/index.php?topic=100359.0
Are you also running Microsoft Windows Essentials antivirus at the same time? Are you using a registry cleaner?
I'm usually pretty good at fixing problems with my PC but this one has me completely stumped. IE 8, XPsp3, Office 2007.
When I first boot the machine everything is fine. As I browse email and navigate the web over about a 10 minute span, strange things start to happen. When I hit a favorites folder in the favorites bar, the drop down appears but several items have missing text. If I hit it again it gets worse, even more items are missing text. Each time more and more items loose the text. When I exit IE the text on the desktop icons has turned black. So then I start Excel and I get error message boxes with no text and no buttons. As I X out of these I start getting instruction memory violation errors. I do manage to exit out of Excel, when I try go back to the web IE won't launch, the screen flashes a blank fully maximize window and then closes immediately. I have to re-boot to get the machine back to normal but it lasts about 10 minutes and starts doing the same thing all over again.
I have run a Windows Essentials security scan, I scanned the C drive with Avast antivirus, I scanned the Registry it was squeeky clean, ran CHKDSK, ran SPyware Doctor, deleted the IE temp files and cookies, and ran hardware driver updates. Everthing reported a PERFECT machine.
I am completely stumped. Thanks in advance for any help!!

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