Symantec have published an article about why since January 7th your computer slows down and Microsoft Word and Excel will not start. Rob - this could be your problem? I noticed that around this date our Internet bandwidth was running at 100% used! The workaround is to disable Certificate revocation....
1. Close all programs.
2. Start Internet Explorer.
3. Click Tools > Internet Options.
4. On the Advanced tab, scroll down through the list box to the Security section.
5. Deselect the "Check for publisher's certificate revocation" option
6. Click OK and restart the computer.
