STORE.EXE is degrading performance

Ah … the infamous STORE.EXE process. While this process may look malicious, it is actually an Exchange service. The STORE.EXE process is the service that manages all of the information stores (databases) on an Exchange server.

It is not uncommon to see the STORE.EXE process consuming a large amount of memory; on busy machines, it will consume much of your processor resources as well. There are ways to optimize system resources for the STORE.EXE process.

If you are running an Exchange mailbox server that has 1 GB or more physical memory (RAM), you should enable /3GB switch in the boot.ini file. This is supported on all version of Windows Server 2003.

While your end users are not generating the high volume of traffic that you are witnessing on your server, spammers are. It is estimated that up to 80% of all mail received by an organization is spam. Therefore, it is likely that your antivirus/antispam server will be busy handling this. In your case, that is Exchange Server.

The reality is that GroupShield and SpamKiller are actually contributing to your STORE.EXE problem every time they run, by accessing mailboxes and scanning mail items, because they both utilize the STORE.EXE process to do so.

I think you would be a good candidate for either a network appliance or hosted service that can perform your antivirus/spam filtering for you, so that your Exchange server doesn't have to.

The answer indicates that the /3GB switch can be used with any implementation of Exchange Server 2003. I don't believe this is the case. For Exchange 2003 that accompanies Windows Small Business Server 2003 (Standard Edition at least), Microsoft PSS says that the /3GB switch not only shouldn't be used, but can indeed cause issues.
—Rick N.

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