My mother in law's PC has McAfee installed. On boot-up It runs the security center, during the security center process, I get a "DNS Error Cannot find server".
I close the form and essentially the PC runs normal after that. Does something need to be refreshed...She only goes online via AOL. Thats all she does with the PC. Any ideas.

The Security Center is trying to connect to McAfee to get the latest updates.  If your mother-in-law is only connecting to AOL (I'll assume dial-up), then the only time McAfee can get the updates is when she is online.  The DNS error is popping up because there is no connection to the world until she manually connects to AOL.

The default config for McAfee is to check when she goes online, and she probably won't even see the updates while she is online.

Short answer - I wouldn't worry about it.  The updates will occur when she connects, and she has virtually no exposure to threats when she is not connected.

Some people may suggest turning off automatic updates, or allowing McAfee to wait until a connection is detected - I've seen these options fail on other software, and if it is not configured properly, you can have more issues.

Hope that helps...

Mike Molenda - TAC Analyst

RSA Corp - Houston, TX
Technical Assistance Center
http://www.rsacorp.com