The toolkit comprises of:

• SSL Diagnostics: Diagnoses problems related to Secure Sockets Layer (SSL) issues.
 
• Authentication and Access Control Diagnostics: Diagnoses permission or security problems.
 
• Exchange Server SMTPDiag Tool: Gathers data for your SMTP server that is included with IIS.
 
• Log Parser: Sifts through thousands of log files quickly.
 
I would certainly recommend having a look at these tools as they can be very useful in quickly diagnosing problems with IIS.
Diagnostic Toolkit

Gavin