LazyWriter: warning, no free buffers found.
SQL 2005, 9.0.3042
Got this in my ERRORLOG, along with a ton a memory messages not worth repeating here.
8GB RAM in the box, SQL Server set to dynamically allocate, and using 6.3 gb.
SQL was not allowing connections, giving the misleading "remote connections are not allowed/TCP" messages (translated: "something bad happened")
Solution (as seen in other places, but not many)...hard reboot of the server, bring up SQL, configure max memory to 6GB (anything other than dynamic, but leave some for the O/S).
No fries...took 30 minutes to get to the resolution. Dessert maybe :)