Topic Last Modified: 2005-11-18

The Microsoft® Exchange Server Analyzer Tool queries the Win32_Directory Microsoft Windows® Management Instrumentation (WMI) class to determine the value of the Encrypted key for the Simple Mail Transfer Protocol (SMTP) PickUp folder. If the Exchange Server Analyzer finds the value for Encrypted set to True, a warning is displayed.

When messages arrive at the Exchange computer through the SMTP service, the data is written to the hard disk as an .eml file. By default, these files are stored in the <drive>:\Program Files\Exchsrvr\Mailroot folder on the same partition that Exchange is installed on. If the folder where the SMTP PickUp data is stored has file encryption turned on, Exchange performance may be severely degraded. Therefore, encrypting the folder where the SMTP PickUp data is stored is not supported.

If you receive this warning, you must turn off encryption on the folder where the SMTP PickUp data is stored, or you must move the SMTP PickUp data to a non-encrypted folder.

Microsoft does not support the storage of Exchange data files on an Encrypting File System (EFS) encrypted volume. When you store your Exchange data files on an encrypted volume, the additional overhead significantly affects Exchange performance. Exchange data files include the following files:

To help secure your Exchange data files, it is recommended that you prevent unauthorized access to the Exchange computer and that you use the S/MIME message format to encrypt message data.

To resolve this error, you must either turn off file encryption on the PickUp folder, or move the PickUp folder to a location where encryption is not enabled.

To turn off file encryption on a given folder

  1. Right-click the folder where you want to turn off file encryption, and then click Properties.

  2. On the General tab, click Advanced.

  3. In the Advanced Attributes dialog box, clear the Encrypt contents to secure data check box, and then click OK.

For more information about moving the PickUp folder, see the Microsoft Knowledge Base article 822933, "How to change the Exchange 2003 SMTP Mailroot folder location" (

For more information about Exchange Server data files and EFS, see the Knowledge Base article 834638, "Information about the storage of data files on an encrypted volume in Exchange Server" (

For information about how to secure messages in Exchange Server 2003, see the Exchange Server 2003 Message Security Guide (