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Troubleshooting Exchange Server error messages

When Exchange Server returns a cryptic numerical error message, do you know what to do? This tip explains a three-tier approach to deciphering and troubleshooting Exchange error codes.

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When Exchange Server returns a cryptic numerical error message, do you know what to do? In this tip, I explain a three-tier approach to deciphering and troubleshooting Exchange error codes.

Windows Event Viewer

The first place to check for additional information is the Windows Event Viewer. Some errors get logged to the Windows Application Log, where you can simply double click on the error to receive more information about it and maybe even a link to a related Microsoft Knowledge Base article.

Microsoft Exchange Server Error Code Look-up Tool

Unfortunately, many Exchange Server errors aren't logged by the Windows Event Viewer -- especially those related to running ESEUTIL or ISINTEG. .

If Exchange Server gives you an error code, but no corresponding message or event log entry, try using the Microsoft Exchange Server Error Code Look-up Tool to troubleshoot. When you provide the Error Code Look-up Tool with a specific error number, it will tell you what that number means.

The utility is a part of the Exchange Server Support Tools, located on the Exchange installation CD in the \SUPPORT\UTILS\I386 folder. If your Exchange installation CD is missing the Support Tools for some reason, you can download the error utility here.

The download consists of an 809 KB executable file named ERR.EXE. Simply run this file to extract the ERR.EXE utility. To run it, enter the ERR command followed by the error number -- just be sure to put a minus sign in front of the error number or it won't work.

Sometimes Exchange Server will produce multiple error codes related to a single problem. In this type of situation, you can get a clearer picture of what's going on by querying all the error codes simultaneously.

For example, suppose that Microsoft Exchange gave you a 1811 error and a 1018 error (these are random codes, not a real-life situation). If you wanted to troubleshoot the problem, you could use the following command:

ERR -1811 -1018

The tool would then create a report that gives you information about both errors, as shown in Figure A.

Figure A: You can query on multiple error codes.
Figure A

Hopefully, the information returned by the error utility will be comprehensive enough to help you to determine what the numbers mean and how to solve the problem. Sometimes, though, the utility won't have a listing for a particular error. I don't know why this is, but I have had several real-life troubleshooting sessions in which Exchange gave me an obscure error number that the Microsoft Exchange Error Code Look-up Tool did not recognize. Microsoft has improved the utility over the last couple of years, but don't expect it to always have the answers.

Microsoft Knowledge Base for Exchange Server

In Figure A, we see that 1018 is a checksum verification error. The error utility told us the meaning of the error code, but now how do we figure out how to fix it?

A logical next step in the troubleshooting process is to consult the Exchange section of the Microsoft Knowledge Base, and perform a search on error 1018.

As you can see in Figure B, the first result returned is an article titled "Support Webcast: Microsoft Exchange: Understanding and Resolving Error -1018," which will help us complete the administrative troubleshooting process.

Figure B: The Exchange Server portion of the Microsoft Knowledge Base is an excellent self-help resource.
Figure B

About the author: Brien M. Posey, MCSE, is a Microsoft Most Valuable Professional for his work with Exchange Server, and has previously received Microsoft's MVP award for Windows Server and Internet Information Server (IIS). Brien has served as CIO for a nationwide chain of hospitals and was once responsible for the Department of Information Management at Fort Knox. As a freelance technical writer, Brien has written for Microsoft, TechTarget, CNET, ZDNet, MSD2D, Relevant Technologies and other technology companies. You can visit Brien's personal Web site at

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