Access Violation in Mspadmin.exe with ISA Server with Multiple IP Addresses on an External Interface

On computers with any of the following configurations, Internet Security and Acceleration (ISA) Server services may not start: You may receive one of the following error messages: No other configurations were tested for this problem.

This issue applies to active interfaces; if your configuration does not match the table above and the ISA Server services start but a user later creates a virtual private network (VPN) connection to the server that is running ISA Server, or if the ISA Server computer dials out with VPN or a modem, causing it to have an additional IP address, the ISA Server services may stop working.

The problem is initiated by the Bwserver.dll file in CreateInterface because of bad pointer math when enumerating addresses.

A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language. The English version of this fix should have the following file attributes or later:

One possible workaround is to clear the QoS Packet Scheduler check box for all interfaces in Network properties. This does not affect ISA Server bandwidth control functionality.

Microsoft has confirmed that this is a problem in Microsoft ISA Server 2000. This problem was corrected in ISA Server 2000 Service Pack 1.

After you apply this hotfix, three redundant values may be added into the Registry, which will need to be fixed in order for IIS to work properly. For more information, refer to the following article in the Microsoft Knowledge Base: