Diagnostic Tools for IIS

A couple of days ago, I ran across a couple of very handy little tools that I had previously been unaware of: the IIS Diagnostics Toolkit, and the SSL Diagnostics Toolkit. Technically, the SSL Diagnostics Toolkit (ssldiag) is part of the IIS Diagnostics Toolkit (iisdiag), but it’s actually been updated since iisdiag was released, and if you’re trying to troubleshoot SSL issues, you’ll want to download and install it separately. The tools are small and straightforward to use, and they’re free!
I ran across these tools trying to troubleshoot an OWA problem – after a rebuild on an Exchange box, OWA and Exchange ActiveSync would not work. A bit of digging revealed that IIS didn’t seem to be responding to any HTTPS requests at all. After digging around a bit and finding these tools, I ran a quick SSLDiag check, and it immediately told me that the SSL certificate that had been installed in IIS did not have a private key associated with it, which meant that IIS could not generate any encrypted information to send back to the requesting client. We installed a new cert, and the site started working as expected.

So now I have another set of tools that I’m going to include as defaults to install on a new server build in addition to the Support Tools from the server install CDs. Very handy tools to have.