Unable to connect to localDB in VS2012 – "A network-related or instance-specific error occurred while establishing a connection to SQL Server..."

Question

This is strange as I'm able to connect to localDB through SSMS 2008R2 with the same connection string ("Data Source=(LocalDB)\v11.0;Integrated Security=true")

Only C# code is unable to connect, I have tried increasing login time with Connect Timeout=60 but no luck.

I have also tried specifying the database Initial Catalog=<databasename> where the <databasename> is the one I have created on localdb via ssms.

Any pointers as to why is this not connecting?

Solution

Any chance it is because you forgot to double-escape the backslash? Did you try this:

"Data Source=(LocalDB)\\v11.0;Integrated Security=true"

Or even better, you could just use the @ mark to disable character escaping for the entire connection string:

@"Data Source=(LocalDB)\v11.0;Integrated Security=true"

Comments

[Varun K]

Ah, this is really the trick. Why does it require double \\? really strange .. Thanks! it worked.

[Varun K]

it seems \v is a special character!

[Krzysztof Kozielczyk]

Exactly! Without the double-escape the \v is considered a single (and special) character. You could also use @ (in C#) to avoid escaping whatsoever, I had updated my answer to reflect it.

[J. Andrew Laughlin]

Also, it should be noted the escape character will prevent SSMS from making the connection to LocalDb.

[DrCopyPaste]

@J.AndrewLaughlin Exactly! Just use the @ to disable escaping and make copy-pasting involve less thought :D