Did you just install SP3 and/or do a Repair Install of Windows?

What anti-virus application or security suite is installed and is your
subscription current? What anti-spyware applications (other than Defender)?
What third-party firewall (if any)? Were any of these applications running
in the background when you installed ___?

Has a(another) Norton or McAfee application ever been installed on the
computer (e.g., a free-trial version that came preinstalled when you bought
it)?

December wrote:
...without having changed any settings all my email has red x's
in place of links and nothing I've tried helps. I am still able to view
ordinary pictures embedded in email or sent as attachments...

I'm running OE6 w/XP on a Dell Inspiron530...