Solve the problem that the Exchange server can't send information

In the Exchange environment, there are many reasons why information cannot be sent. For example, the communication line may be faulty, or the Domain Name Resolver (DNS) may have problems and cannot resolve the receiving domain. In either case, information that cannot be sent can cause communication traffic to crash in your employees, suppliers, and customers. Fortunately, you do have some means of controlling how Exchange handles messages that cannot be sent.

Access to Unsent Information

In Exchange Server 2003, the option to not send information is under the virtual server level control in the SMTP level. To access options that cannot be sent:

1. Open Exchange System Manager and go to the management group through the console tree, then go to "Your Management Group", then click "Server" -> "Your Server" -> "Protocol" -> "SMTP" -> "Default SMTP Virtual Server".

2. Right-click on "Default SMTP Virtual Server" and select "Properties".

3. Click the "Send" tab to browse the options for unsent messages.

As a default, if the Exchange server can't send messages, it will retry within 10 minutes. If Exchange still can't send the message, it will wait 10 minutes before the next attempt to send. If the message still cannot be sent at this time, Exchange will retry for the third time.

At this point, if the information is still not sent, in the next two days, Exchange will try to send a test every 15 minutes. If two days have passed and Exchange still can't send the message, then a report about the unsent is sent.

In Exchange Server 2003 SP1, the Windows operating system sets the bad mail (BADMAIL) directory to disabled. However, a copy of the information will still be placed in the BADMAIL directory in earlier versions of Exchange. The capacity of this information in the BADMAIL directory is unlimited, until a large amount of unsent information is placed in the BADMAIL directory, so that the server has insufficient disk space.

Options for unsent mail

Now that you know how Exchange handles unsent messages, let's see how you can modify Exchange. . In the Send tab in the default SMTP virtual server properties, you are allowed time for the first, second, and third subsequent retries. You can also control the expiration time of these messages.

Another aspect worth mentioning in this tag is the Delay Notification setting. As a default, Exchange is set up as shown above. If the message cannot be sent within 12 hours, the sender will receive a message indicating that the message has not been sent yet, but it is not necessary now. It is resent. You can change the notification time from 12 hours to any time that suits your needs.

Setting BADMAIL Options

In earlier versions of Exchange, the BADMAIL directory played a black hole role for unsent messages. I think it's wise to disable the BADMAIL directory in the Windows operating system because most administrators never use the BADMAIL directory. But if you really need to use it, you can enable the BADMAIL directory by modifying the registry and prevent it from growing to an unreasonable size.

Before showing you how to set the BADMAIL option, remember to modify the registry is very dangerous. Once you make a mistake, you may destroy your Windows operating system and your application. So, before you continue the operation below, please backup the entire system.

Next, you can access the BADMAIL settings in the HKEY_LOCAL_MACHINESystemCurrent Control Set ServicesSMTPSVCQueuing key.

Once there are two different registry keys there, you should pay attention to the following (if they don't exist, you need to create these keys):

1. The first key value is the DWORD value named MaxBadMailFolderSize.

This key value indicates how many KB sizes the BADMAIL folder can add before the old project is discarded. The BADMAIL folder is disabled in Exchange Server 2003 SP1, so the default value for this value is 0. If you want the BADMAIL folder to revert to the way it was before SP1 and allow it to grow without limit, then change the value to -1. Otherwise only the size of the folder is defined. For example, if the value is 3072, then the size of the BADMAIL folder is allowed to grow to 3MB.

2. Another key that needs your attention is the DWORD value named BadMailSyncPeriod.

This value tells Exchange how much time it needs to check for changes to the BADMAIL folder size. If you manually delete some items in the BADMAIL folder, Exchange will not immediately find that these items no longer exist until it runs the BADMAIL synchronization program. This value tells the Exchange how long it takes to run the synchronization program.

The synchronization period is set to 0, which means disabled. But if you want, you can also set it to -1, which allows Exchange to run in the same way as SP1. You can also specify the interval to run the sync program as a few minutes. If you choose to use the BADMAIL folder, my recommended BADMAIL sync program runs every 10-15 minutes.