Exchange Server Error.

RESOLUTION
A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that are experiencing this specific problem.

To resolve this problem, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:
http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS

NOTE: In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The English version of this fix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.
Date Time Size File name Platform
-----------------------------------------------------------
16-Jul-2001 12:05 36,112 Ntlmssps.dll I386 - 128-bit (SRP)
23-Sep-1999 11:04 59,152 Security.dll I386 - 128-bit (SP6a)
16-Jul-2001 12:05 36,112 Ntlmssps.dll I386 - 56-bit (SRP)
18-Nov-1999 12:04 59,152 Security.dll I386 - 56-bit (SP6a)
NOTE: Because of file dependencies, this hotfix requires Microsoft Windows NT 4.0 Service Pack 6a.

WORKAROUND
To work around this problem, install the hotfix that is mentioned in the "Resolution" section. This upgrades the computer to 128-bit security.

If you must use the 56-bit versions of the DLLs in Windows NT 4.0, you can manually replace the Schannel.dll and Ntlmssps.dll files with the 56-bit versions from the SRP:
Extract the files from the SRP. Use this command q299444i -x.
Rename the current Schannel.dll and Ntlmssps.dll files in the %SystemRoot%\System32 folder.
Copy the SRP versions of the Schannel.dll and Ntlmssps.dll files to the %SystemRoot%\System32 folder.
STATUS
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.
MORE INFORMATION
This problem may occur with Microsoft Exchange 5.5 administrative programs connecting to Exchange 5.5-based servers. This causes the following error message:
DS_E_COMMUNICATIONS_PROBLEM
When you join a Microsoft Exchange 2000 server to a Microsoft Exchange Server 5.5 site, you may receive the following error message:

Error code 0XC103FC93 (64659): Could not bind to the Microsoft Exchange Directory server EXCHANGE1.
The Microsoft Exchange Server computer does not respond. For additional information, click the article number below to view the article in the Microsoft Knowledge Base:
311401 Windows 2000 Security Rollup Package 1 (SRP1), January 2002

For additional information about how to install multiple hotfixes with only one reboot, click the article number below to view the article in the Microsoft Knowledge Base:
296861 Use QChain.exe to Install Multiple Hotfixes with One Reboot
The information in this article applies to:
Microsoft Windows NT Server 4.0
Microsoft Windows NT Server 4.0 SP6a

PS
don't you have more clues in the event log? exchange and 2000?
PPS
call microsoft, betcha this one will qualify for free support...

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