Ok, if you're like me and aren't the smartest cookie in the jar, something like specifying a connectionString in a web.config file can be maddening.  Of course, it doesn't help that there are literally 123 billion possible ways to do a connection string...but I digress.

While searching for an answer, I ran across a pretty neat little technique that will make the development of your connection string quite painless.

First, open Explorer, and create a new file. Now, rename the file to X.UDL. Double-clicking this file will open up a Data Link Properties dialog window.

The super nifty thing about the DLP is that you can actually create a full-on connection to a datasource, and test out various settings.  Nice.

But the really beneficial part (well, besides verifying that, yes, this particular service account does, in fact, have access to SQL Server...) is the "All" tab.  Here, you'll see all of the properties of your connection.  While nice information, this is super sweet because these properties are precisely the parameters that you need to enter into your web.config connection string in order to make SQL Server happy.  That's awesome, and a huge time saver if building connection strings isn't something that you do on a routine basis :)