Blocks instead of letters.

Some times my computer will display blocks instead of letters on web site headings and discriptions. Do I have a virus or what?

 

My OS is Windows XP and my IE is version 6. I checked that thread and tried the things mentioned and it didn't work.
So far I've noticed the bars on a few of the site links and in the discriptions below the links. But not on my browser bar as mentioned in the thread link.

 

= http://www.softpedia.com/get/Tweak/Browser-Tweak/IEFix.shtml
= http://www.majorgeeks.com/download4467.html
http://www.aumha.org/win5/kbie.php
How to reinstall or repair Internet Explorer and Outlook Express in Windows XP = http://support.microsoft.com/default.aspx?kbid=318378

Repair or Reinstall IE6 and Outlook Express 6 = http://www.theeldergeek.com/repair_reinstall_ie_and_oe_6.htm

Gewneral IE help = http://inetexplorer.mvps.org/ie.html

http://www.generation.net/~hleboeuf/ieindex.htm

Microsoft Internet Explorer 6.0 = support.microsoft.com = http://support.microsoft.com/default.aspx?scid=fh;EN-US;ie