My prior post here is #8 in this thread.
There are also other threads on this communication issue in this category. After reviewing those and after 2 more reboots did not restore the functionality of SiteAdvisor, I did the following.
Running XPPro SP2. IE6. All patches current. Running the free version of SiteAdvisor.
Note that SiteAdvisor is the only McAfee software I had installed on my computer, so I felt free to remove anything referencing McAfee or SiteAdvisor. If you have other McAfee products on yours, I would recommend not removing the McAfee folder.
-I uninstalled SiteAdvisor in Add/Remove Programs.
-I deleted the following folders:
--McAfee in C:\Documents and Settings\All Users\Application Data
--SiteAdvisor in C:\Documents and Settings\All Users\Application Data
--SiteAdvisor in C:\Program Files (had to boot to Safe Mode to get rid of this one).
Rebooted.
Ran a registry cleaner program to get rid of any leftover registry entries so I could start "fresh" as though SiteAdvisor had never been installed on my computer. I did this because, since McAfee doesn't seem to know what's causing this problem yet, I wanted to remove everything related to SiteAdvisor on my computer in order to avoid a remaining setting or .dll file causing the problem to re-occur.
I reinstalled SiteAdvisor from
http://www.siteadvisor.com/download/ie.html (note that I'm again using the free version).
So far so good, and it's working. I'll report back if problems occur or in a week if no problems occur.
Good luck with it,
Pat