HELP with AOL Connectivity Problem

My husband uses AOL and has been getting errors - Computer could not get an internet connection. We are connected to internet through a linksys router and an Embarq modem. He also gets a message: PNH Sync time out, host is not responding. When he gets these error messages he cannot get on internet via Internet Explorer either. I have tried 99% of AOL's connectivity repairs and none have worked. It seems that the only thing that works is to shut down the computer and restart. For some reason this seems to clear whatever is causing the problem. AOL techs have not been helpful.

I have restarted the router, modem, double checked the cables, doubled checked network settings, internet connections, etc. Anyone have ANY suggestions? :cry