Someone else posted this error before so you can read my previous response.
what version of mojoPortal, what operating system, what version of MS SQL.
Is the database on the same machine as the web server, is it your machine or hosted?
I would make sure you have all the service paks installed for MS SQL, other than that it seems like probably a slow connection or response from the database.
I would also review your log under Key Icon > System Log
or webroot/Data/currentlog.config file
Hope it helps,