# Features (EN) RackCorp UMS is feature-rich, made for multi-tenanted environments such as ISPs, Managed Service Providers, Governments, and multinationals who need to run multiple tenancies within a hosted environment.
**Feature** | **Available / Description** |
Multi-domain | Unlimited domains allowed |
Contacts | Unlimited Contacts allowed |
Calendar | Unlimited Calendars allowed |
Tasks | Unlimited Tasks allowed |
Full-Text Search (including attachments) | Yes (v 1.3+) |
Attachment Preview | Yes (Text, Images, some other) |
POP/IMAP/SMTP Support | Yes (Encrypted versions of these protocols, optional to turn on unencrypted) |
Deleted Items / Trash | Yes (default 30 days) |
Granular account access control | Disable deleting / sending emails vs read-only access |
Auto-responder | Yes |
Server-side mail sort | Yes, using sieve mail filters (configurable from web) |
Scalable | Active-active topology allows massive scaling |
Fault Tolerance | Node auto-sync, multi-site, load balanced |
Delivery notifications | Yes (where supported by recipient) |
Global Address Book | Yes |
CardDAV, CalDav, iCal Support | Yes, Yes, Yes! |
LDAPS integration | Yes |