I'm running a web server on IIS7. I've been playing around with DNN for the first time really. I have a DNN portal that has3 active sites on it. They're business sites that get minimal traffic really. Along with DNN, I'm hosting several other non-DNN blog sites (ASP.Net 4.0 sites). I haven't had problems with these sites before, but after I started running DNN, I started getting Database connection problems from these sites. They sporadically encounter errors connecting to the database. 

I put in some Try\Catch blocks to get the error messages and they say:

"Timeout expired. The timeout period elapsed prior to obtaining a connection from the pool. This may have occurred because all pooled connections were in use and a max pool size was reached."

My SQL Server is more or less installed with the default options. The remote connection count is set to "0" or unlimited. My connection strings in my code are standard and use sql authentication (server, database, uid, password).

This problem seems to happen about 50% of the time. Sometimes the site works, sometimes it doesn't. It keeps tripping my monitoring software with 500 errors when the sites go down. While this is happening to those sites, my DNN sites work fine, and it didn't seem to happen until I started running DNN.

Is there something about DNN or how DNN connects to my database server that could be causing this problem?