Uploading In IE6 With Fiddler is Faster?

In our asp.net application we have an upload feature. When Fiddler is running on the client (with Act as a system proxy) the upload is quick (10megs in 20 sec). however, when Fiddler is not up on the开发者_StackOverflow client it's taking about 5 minutes. Any one have any suggestions?

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Converting to answer

Fiddler isn't replacing that setting, but as a local proxy, it's buffering the complete POST request locally (so the small buffer doesn't matter) and then blasting it to the server as quickly as the server will take it. The send buffer size was increased in later browser versions.

For IE6, see the steps in http://support.microsoft.com/kb/329781 to adjust the buffer size.