| Company/Organisation | Users | Servers | Contact | Details | 
    
        | SAPO Mail (Portuguese ISP) | 1.65M Webmail users | 11 Webmail+imap proxy servers / 2 MySQL servers / 6 Dovecot IMAP servers (dual 3.0GHz Xeon P4, 4GB RAM) | Nuno Loureiro | Running Horde/IMP/Turba/Kronolith/Ingo - Splitted from CVS HEAD on Oct 2003. Running Zend Platform.  | 
    
        | SAPO Mail BETA (Portuguese ISP) | 60,000 Webmail users and growing | 2  Webmail+imap proxy servers / 2 MySQL servers / 6 Dovecot IMAP servers (dual 3.0GHz Xeon P4, 4GB RAM) NOTE: All the backend servers (sql, imap, ..) are the same for Webmail and Webmail Beta (see previous entry) | Nuno Loureiro | Running Horde/DIMP/Turba/Kronolith/Ingo - CVS HEAD! Running Zend Platform.  | 
    
        | versatel.nl | 250,000 webmail | 5 x dual Xeon 3,2 Ghz 4GB running Apache, imapproxy and perdition on Debian Sarge | Richard Zuidhof | Horde 3.0.x / IMP 4.1.x, ionCube | 
    
        | University of Michigan | 113,000 | IMP / Horde: 5 x Dell Poweredge 1750 (dual 3.0GHz Xeon P4, 4GB RAM), 9 x SuperMicro 5013S-8 (dual 3.6Ghz Xeon P4, 4GB RAM);  MySQL: 2 x Western Scientific (dual 3.0Ghz Xeon P4, 4GB RAM, RAID 1+0) | Liam Hoekenga | eAccelerator , Cyrus IMAP, UP-IMAPProxy, memcache based sessions | 
    
        | Columbia University | 85,000 | IMP / Horde: 9 x SunFire v240; Oracle: 1 x SunFire T2000; Cyrus Frontends: 12 x HP DL360; Cyrus Backends: 18 x HP DL360 pairs | Matt Selsky | eAccelerator , Cyrus IMAP, UP-IMAPProxy | 
    
        | University of Frankfurt | 40,000 |  | Mail Support Team | Established their own Horde user guide wiki | 
    
        | University of Giessen | 30,000 |  | Mail Support Team | Offer Roundcube and Squirrelmail as well | 
    
        | Ghent University | 30,000 | Debian Etch on some Sun machine |  |  | 
    
        | University of Wuppertal | 15,000 |  |  | Horde 4. Deals with about 10.000 logins per day. | 
    
        | Graz University of Technology | 13,000 | Horde 4, Sun Fire X4100 2x2.4 Ghz Dual-Core AMD Opteron, 4Gb Ram, 2x Sun Fire V20z 2x2200 Mhz AMD Opteron 4Gb Ram, 2 redundant Cisco loadbalancers CSS11503 with cyrpto-cards for SSL accelleration, 2x Sun X4600 4x3.0 Ghz Dual-Core AMD Opteron, 16Gb Ram for mySQL backends in Master-Master replication mode | webmail | SSL is handled by the crypto card on the loadbalancer, PHP is accellerated by xcache, up-imapproxy | 
    
        | Harvard University, Faculty of Arts and Sciences | thousands | 4 Compaq Tru64 |  | Details | 
    
        | University of Texas at Austin, Department of Physics | 1,000 | Dell Poweredge 2650 server, dual Xeon 3.0 Ghz,  1 GB memory, 2 S/W Raid1 volumes | Eric Rostetter |  | 
    
        | National Portuguese Government Agency | 1,000 | 8 Mail Servers (Exchange) and 1 Webmail Server (Apache/SSL) |  |  | 
    
        | Linux Information Systems AG | hundreds |  | Matthias Rolke | We offer a customized horde groupware setup as a frontend for the Kolab Groupware that includes dimp, turba, kronolith, mnemo, nag and ingo. The complete backend consists of Kolab, OpenLDAP, postfix, Apache2 and sieve.  | 
    
        | Case Western Reserve University, EECS Department | hundreds | 2 Sun X1 and 1 Sun V280R | Simon Kuhn |  | 
    
        | NYU School of Medicine |  |  |  |  | 
    
        | Universidad Tecnica Federico Santa Maria |  |  |  |  | 
    
        | University of Colorado at Boulder |  |  |  | Details | 
    
        | Yale University |  |  |  |  |