I was trying to install the silverlight chat module today.  I backed up my web.config file, then took to modifying it.  I made all the changes recommended on this page (http://dnnsilverlight.adefwebserver.com/FAQ/InstallingSilverlight/tabid/80/Default.aspx), and my site broke.  It would still load, but images didn't work, and the OWS modules didn't work right.  Backup to the rescue. 

I tried installing this module (http://www.adefwebserver.com/DotNetNukeHELP/Misc/LinqPrep) which is supposed to change the web.config to prepare it for linq.  It installed, but didn't work.  It gave an error about permissions, and couldn't read or make changes to web.config.  Ok. 

I added the following lines to the <system.webserver> section of the web.config:
<staticContent>
     <mimeMap fileExtension=".EXTENSION" mimeType="TYPE/SUBTYPE" />
   </staticContent>

This resulted in breakage of the site again - no images, no form.... all funky.  Once again, I restored web.config with the backup, but now the site does nothing.  It just shows me a blank white page, and the spinny thing that says it's still working just spins infinitely.  I tried changing customerror mode to off, hoping to get something, but alas, there are no errors to show - just a blank page.

I am able to navigate to mysite/install/install.htm, so I know the dns is working, my url is going to the right place, etc.  This has affected all of the domains/sites that are pointed to this instance of dnn. 

Can anyone suggest where to go with this? 

Problem resolved - I re-uploaded the upgrade files and the sites all work again.