Can Exchange Server 2003 databases be restored without using the Volume Shadow Copy Service and the Exchange writer?
No. During any restore operation managed by the VSS, the Exchange writer performs steps during both PreRestore and PostRestore events. The Exchange writer sets VSS_WRITERRESTORE_ENUM to VSS_WRE_ALWAYS to inform the requesting backup/restore application that the VSS must always be used to backup or restore Exchange Server 2003 data. Restoring data from a backup created using the VSS without also using the VSS is not supported, and will consequently fail.