Internet Explorer 6 SP1 may stop responding when you try to connect to a secure Web site

When you try to use Microsoft Internet Explorer 6 Service Pack 1 (SP1) to connect to a secure Web site (https://), Internet Explorer may stop responding (hang).

This problem may occur when the use of Federal Information Processing Standard (FIPS) encryption algorithms is enforced through the Computer Configuration Security Options policy.

Some Secure Sockets Layer (SSL) implementations send a zero-length packet as the first message over an SSL connection. This behavior occurs only when a block cipher such as Triple Data Encryption Standard (Triple DES) is used, and is intended as a workaround for a known block cipher chaining vulnerability. The Internet extensions for the Wininet.dll file does not interpret this zero-length packet correctly.

To successfully connect to a secure Web site, disable the system policy that requires FIPS-compliant algorithms. To do this, follow these steps:

1. Click Start, and then click Control Panel.
2. Click Performance and Maintenance.
3. Click Administrative Tools.
4. Double-click Local Security Policy.
5. Expand Local Policies.
6. Click Security Options.
7. In the Policy list, double-click System cryptography: Use FIPS compliant algorithms for encryption, hashing, and signing.
8. Click Disabled, and then click OK.
9. Restart your computer.

For additional information, click the following article number to view the article in the Microsoft Knowledge Base: For additional information, click the following article number to view the article in the Microsoft Knowledge Base: