Moved from Home to work and went to fire up my project and after long pause

"The provider did not return a ProviderManifestToken string"

or even More Abscure

ProviderIncompatable Exception

Now after 20 mins of chasing my tail re different ver of EntityFramework 4.1 vs 4.2...blahblahblah

Look inside at the inner exception

A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible

DOH!!!!

Or a clean translation is that it cant find SQL or is offline or not running. SO check the power is on/Service running or as in my case

Edit web.config & change back to Work SQL box

Hope you dont have this pain as the default errors @ the moment suck balls in the EntityFramework 4.XX releases

Cheers