Microsoft Jet databases are managed by  ESENT or ESE. When you place a Jet database on a compressed drive, you may experience write-through delays, which can cause database corruption.

Jet database and related files include DIT files, logs, checkpoints and temporary databases:

Active Directory (NTDS)                              File Replication service (FRS)                              Windows Internet Name service (WINS)                              DHCP                              Security Configuration Engine (SCE)                              Certificate Server                              Terminal Services Session folder                              Terminal Services Licensing service                              Catalog database                              Help and Support Services                              Directory Synchronization service (MSDSS)                              Remote Storage (RSS)                              Phone Book service                              Single Instance Store (SIS) Groveler                              Windows NT Backup/Restore                              Exchange store                              Microsoft Exchange folder (SRS and DXA)                              Key Management service (KMS)                              Instant Messaging                              Content Indexing