Do you use Fiddler to inspect the HTTP traffic?
You may be faced with the following problem: since we started using the beta of the IE7 browser we started experiencing problems when monitoring the requests sent to http://localhost or http://127.0.0.1 - the requests were not reported by the Fiddler tool.
It took us some time to understand what was the exact reason for this until we found the workaround for this issue here:
http://www.fiddlertool.com/Fiddler/help/hookup.asp
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Why don't I see IE7 or System.NET traffic sent to http://localhost or http://127.0.0.1?
IE7 and the .NET Framework are hardcoded not to send requests for Localhost through any proxies,...