3/13/00: MICROSOFT IIS 4 VERSUS NETSCAPE COMMUNICATOR 4.7

An incompatibility has arisen between Microsoft's widespread Internet Information Server 4 (note: NOT Microsoft's Web browser, MS Internet Explorer) and international versions of Netscape Communicator 4.7. The bug involves miscommunication between browser and server when Communicator attempts to accept 56-bit digital certificates. IIS 4 does not support 56 bits, and when Communicator tries to step up to 128-bit certificates, it causes an invalid page fault in netscape.exe. The only upside exists for users of the domestic (U.S.) 128-bit version of Communicator, which Netscape claims is immune to the bug. Users of the international versions can work around the problem by disabling 56-bit encryption. Follow these steps:

* In Communicator, select Tools, Security Info. * In the resulting Web page, click the Navigator link in the left column and then select Configure SSL 3 from the right pane. * In the subsequent pop-up menu, remove the check marks from the following two options: "RC4 encryption with a 56-bit key and a SHA-1 MAC" and "DES encryption in CBC mode with a 56-bit key and a SHA-1 MAC". * Click OK twice to finish. Microsoft is still working on the problem with IIS 4.