I encountered an intereseting problem this week.

We have a DNN portal on one of our web servers, not a hosted plan, and everytime the application pool would recycle or restart we would get an 'Under Construction' page (/Install/UnderConstruction.htm) the very first time we navigated to the portal.  If we refreshed the page the portal would work great until the application pool was restarted again.

Looking into the applicaiton event logs on the web server we noticed that everytime we recieved the Under Construction page we would also see two .Net errors in the application even log.  The errors in the event log indicated a failure trying to log into SQLServer.  The login reported in the error messages was [DomainName]\[ServerName]$.

The policy on our web server is to use Trusted connections so our DotNetNuke connection string was: "server=MSSQL01;database=DotNetNuke;Integrated Security=true". Upon seeing the errors in the even log, and not finding any other cause for the errors, we updated our connection string to use a SQL Authenticated login: "server=MSSQL01;database=DotNetNUk;uid=dnnuser;pwd=ourpassword". 

This change fixed our errors.  We can now recycle the application pool as much as we want and the portal comes right backup. So my questions is:

Does anybody know why DotNetNuke would be having problems using a trusted connection during application start up?  We really would prefer not to store our passwords in our web.config file.

Thanks, for any suggestions you may have.