Was your HDD formatted and the OS reinstalled.

If so then you should check the security settings in the IE web browser
Make sure it is set to Medium.

Have you done all the MS Security updates?

You also may want to try a different web browser.
http://www.mozilla.org/

Your browser may also be sending malicious info when you are attempting to
Access a secure site this extra malicious info will cause your request for URL to be halted by the Secure Site

Spy Bot Search and Destroy
http://www.spybot.info/en/index.html

Good Luck