Step 1: What Do You Need?

To get the best performance and the flexibility to expand your mail service, we recommend that you dedicate a computer to function as your e-mail server and that you do not run other servers on the computer.

IMail Server System Requirements

Tip: Before installing on Microsoft Windows 2008 Server, be sure IIS 7 has "Metabase Compatability" enabled. See also Installing IMail Server on Microsoft® Windows 2008

Hardware

TCP/IP enabled network interface card (NIC) with a static IP address
Disk space is dependent on the number of users and usage.

Minimum Requirement

Operating System
Windows 2003 (32-bit)	550 MHz 512 MB RAM
Windows 2003 (64-bit)	1.4 GHz 1 GB RAM
Windows 2008 (32-bit)	1 GHz 1 GB RAM
Windows 2008 (64-bit)	1.4 GHz 1 GB RAM
Windows 2008 R2	1.4 GHz 1 GB RAM

Recommended Minimum by Users

Number of Users	Light Use	Moderate Use	Heavy Use
1 - 25	2 GHz 512 MB RAM(4)	2.4 GHz 1 GB RAM(4)	2.4 GHz 1 GB RAM(4)
25 - 100	2 GHz 1 GB RAM(4)	2.4 GHz 2 GB RAM	2 GHz Dual-Core 2 GB RAM
100 - 250	2 GHz 1 GB RAM(4)	2.4 GHz 2 GB RAM	2 GHz Dual-Core 2 GB RAM
250 - 500	2.4 GHz 2 GB RAM	2 GHz Dual-Core 2 GB RAM	2 GHz Dual-Core 2 GB RAM
500 - 1000	2 GHz Dual-Core 2 GB RAM	2 GHz 512 MB RAM(4)	2 GHz 512 MB RAM(4)
1000 - 2500	2 GHz Dual-Core 2 GB RAM	2 GHz Dual-Core 2 GB RAM	Quad-Core 4 GB RAM
2500+	2 GHz Dual-Core 2 GB RAM	Quad-Core 4 GB RAM	Quad-Core + 4 GB RAM

Light use is defined by the system primarily supporting POP3 users with less than 10% of users accessing mailboxes via web mail and/or mobile devices concurrently.
Moderate use is defined as a mix of IMAP and POP3 users accessing the system with an average mailbox size less than 200 MB and less than 40% using web and/or mobile devices concurrently.
Heavy use is defined as a mix of IMAP and POP3 users accessing the system with an average mailbox size exceeding 200 MB and more than 40% of users using web and or mobile devices concurrently.
Microsoft recommends at least 2 GB RAM for Windows 2008.

System Guidelines for Mobile Synchronization Usage

These are general guidelines and are an approximation based on in-house performance testing. There is no guarantee that the recommendations stated below will exactly match each particular clients needs. These estimates are based on moderate mobile synchronization usage. Initial mobile synchronization and complete resynchronization of data tend to have very high cpu usage, depending on the amount of data being synchronized.

System performance will seriously be degraded should a large number of initial synchronizations happen simultaneously.

It may be necessary to run the IMailSync application pool with multiple processes should there be a large number of mobile users.

Warning: IMailSync, IAdmin, and IClient should never be run in the same application pool. Also, both IClient and IAdmin do not support multiple processes.

Mobile User Count	Mobile System Recommendation
10 Users	2 GHz Pentium 4 with 1 GB of RAM
25 Users	2.4 GHz Pentium 4 with 1 GB of RAM
100 Users	2 GHz Dual Core processor with 2 GB of RAM
250 Users	2.2 GHz Dual Core processor and/or up to 2.8 GHz Xeon Dual Core processor with 2 GB or RAM
500 Users	High end Dual Core or low end Quad Core with 3 GB of RAM
1000 or more users	Quad Core with 3 GB Memory or more

Note: For best performance, we recommend that you make sure the latest updates for the operating systems be employed. Additionally, we recommend NTFS (rather than FAT) file system for increased operability and security.

Tip: IMail Server runs properly on the minimum hardware requirements recommended by the installed operating system. Performance and capacity increases are based on processor speed, RAM, and drive space. As with all server applications, we recommend that you install IMail Server on the fastest and most powerful server that your budget allows.

Software

Microsoft® Windows® 2000 Server, Microsoft® Windows® 2003 Server or Microsoft® Windows® 2008 Server

Note: Do NOT deploy IMail on a Windows 2000 Domain Controller.

Microsoft Internet Information Services (IIS) 5.0 or higher
Windows Script 5.6 (part of Microsoft Internet Explorer 6)
Microsoft Data Access Component (MDAC) 2.6 or later
Microsoft® .NET Framework 2.0

Note: If you are missing any of the above, see the latest Release Notes for links to their sources.