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 that the
Encrypting File System requires significantly impacts the performance of
Exchange. The Exchange data files include all the following files:
.edb files
.stm files
.log files
To help secure your Exchange data files, Microsoft recommends that
you prevent unauthorized access to the Exchange computer and that you use the
S/MIME message format to encrypt message data.
Note
There are no .stm database files in Exchange 2007.
For
additional information about how to configure S/MIME in Microsoft Exchange
Server 2003, see the
Quick Start Guide for S/MIME in Exchange Server 2003. To obtain this guide, visit the following Microsoft Web site: