Unable to open formatted failed request trace log files on an Azure VM

Posted by on Jul 13, 2014 in Asp.net, Azure, Cloud

I recently had a problem whereby I couldn’t view failed request trace logs on an Azure hosted VM. The XML would open, but the XSLT wouldn’t be applied which made the page unreadable. My first thought was that freb.xsl file was missing or corrupt somehow, but after deleting the containing IIS log folder, which causes IIS to regenerate the file it was clear this wasn’t the fault.
After a bit of digging I came to the conclusion that it must be permissions based and stumbled upon this post. Even though I wasn’t getting the content blocked error message, the default internet security settings on azure VM’s are set to high. Therefore, to resolve this you (rather bizarrely) need to add the about:internet page to the trusted sites list:

  • Internet Options
  • Security Tab
  • Click Sites
  • Enter about:internet in the ‘Add this website to the zone” text box and click the add button
  • Close IE and re-open the trce log XML

I’m not really sure why about:internet specifically fixes this, but it worked for me!