This error usually occurs when
- there is an important count of dbs on the server
- or when the db have the autoflag property set to true
To avoid it, you can simply specify the db name when you log in the login dialog box.
UPDATE: as you can see many Startup database event, it means that the autoclose flag is set to true. Change it to FALSE and you will notice great enhancement
http://technet.microsoft.com/en-us/library/bb402929.aspx