For advance security & compliance you may need device & location agnostic, centralised, automated, real-time & tamper-proof secondary storage.
Choose either one or both :
A) Archival of all mails in your domain with data retention as per compliance and e-Discovery to locate & download any mails and/or
B) Backup of select critical mailboxes with One-click-restoration of accidentally deleted mails within select time frame.
Rediffmail users with Advanced Email plan can avail of this facility.