This question is not as simple as it seems to be. I have 64 bit SQL Server 2008 installed on a Windows 7 computer and it works fine when its running.
In the SQL Server Configuration Manager application (also seen in the Windows 7 Services window), the SQL Server instance Start Mode (StartupType in the Windows 7 Services window) is set to Automatic.
The problem that I have is that despite being set to Automatic, the SQL Server rarely starts automatically. I say 'rarely' because it does start sometimes.
At first I thought something must be wrong with the setting, so I set it to Manual and then back to Automatic and this seemed to work for a few days, but that may well have been a coincidence. Then I thought that there might be an error logged in the Windows 7 Event Viewer but there are no SQL Server entries until I manually start it.
Does anyone have any ideas what might be the problem?
My guess is that something MSSQL requires is not ready when it tries to load up. This can happen for a variety of reasons such as dependency on network drives, or start-up security accounts, or a number of other reasons.
Try setting the startup mode from Automatic to Automatic (Delayed).
Take a look at this post over on dba.stackexchange.com for a similar issue with a full blown server running on a SAN and a variety of approaches to work around the issue.
https://dba.stackexchange.com/questions/4936/how-to-delay-sql-server-startup