A search for the first error message only turned up your post that you made on the ASP.NET forums, however, by massaging my query on Google I turn up this result:
here is the google query i used: http://www.google.com/search?hl=en&r...B+system+error
Your second error is easier.
Goto Start --> Run --> inetmgr This starts the IIS MMC
Right click on your website (or application) and select properties. Go to the Directory Security Tab. Tick the Integrated Windows Authentication checkbox. This applies to IIS 5.1 - 6
For IIS 7 check this link:
Also, if you are running Vista, you need to have at least Home Preimum to enable Windows Authentication in IIS. (Home Basic/Starter do not provide this functionality)
Read this if you want to know how to get a correct reply for your question:
.: Wrox Technical Editor :.
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