Can ping IP and Name but cannot browse server, why?

I have a terminal server on my network that, upon occasion, stop being able to browse to a database server that’s on the same physical network (but not a domain member). I can ping the DS from the TS using both the IP and the name but still cannot browse or connect. Restarting the TS resolves the issue. I check the services before restarting and everything automatic is running. The stands out in the event viewer to me that could be causing the issue. Any thoughts?