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Error occurs during SSL connection

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When you attempt to connect to an IIS Web site using an SSL connection, one of the following symptoms occurs, depending on the browser being used:

In Internet Explorer, the following error message occurs:
Internet Explorer could not open the Internet site: <URL>
The data area passed to a system call is too small.
Netscape Communicator stops responding when you attempt to make the connection.

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The browser is trying to use a 128-bit session key, but the Web server is set up to use a 40-bit key.

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Note Due to export restrictions, the 128-bit key strength encryption feature is available only in the United States and Canada.

To resolve this problem, install the 128-bit version of the latest Windows NT 4.0 Service Pack (SP). This will enable the Web server to create 128-bit connections.

Installing the 128-bit version of the Windows NT SP updates the Schannel.dll file, which is used by IIS to create SSL connections.

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More information

For more information about setting encryption strength, copy the following URL to your browser:
For information on how to determine the security strength that IIS is using, see the following article in the Microsoft Knowledge Base:
184311 Remote key request generation affected by Schannel.dll

(c) Microsoft Corporation 2000, All Rights Reserved. Contributions by Kevin Zollman, Microsoft Corporation.

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Keywords: kbpending, kbprb, KB207523

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Article Info
Article ID : 207523
Revision : 6
Created on : 7/7/2008
Published on : 7/7/2008
Exists online : False
Views : 345