could you please suggest any mail system that met these requriments except horde and i recmonded if that can working under windows :
Dear Mr. Amin,
According to our phone conversation, please find below the requirements we need for a Mailing System:
1. Number of active mailboxes: 25.000.
2. Maillists (20.000) with automated generation.
5. Quota management
6. Management GUI
7. Comprehensive logging.
8. Mailbox migration from old system
9. Antivirus / Antispam / Keyword-based content filtering.
10. Users/maillists management API.