Requirements To install XMB your web host must support both PHP and MySQL. If your web host does not have these availible, you will NOT be able to install XMB.
Resource Requirements
On a new installation, XMB uses about 6 MB of disk space. Most forums use less than 20 MB of disk space between both files and the database, and use less than 100 MB of bandwidth a month. Pruning old posts and attachments can keep total disk space to acceptable levels.
XMB 1.9.11 is very CPU efficient in comparison to previous versions and compares very favorably to other forum software. Most web hosts should not see any significant load from XMB until large numbers of users active simultaneously (about 200 simultaneous users).
You can expect a forum with 2,500 users, 125,000 posts, 20,000 attachments, and 35,000 U2U's to use about 400 MB of disk space and about 20 to 25 GB of bandwidth monthly. It is advised that you purchase a dedicated server for a forum with this level of activity.
Web Server
The majority of web hosts use Apache. However, XMB is compatible with any web server capable of running PHP. This includes Windows 2000’s Personal Web Server, IIS 5, 5.1 (Windows XP), and 6 (Windows 2003), and Apache 1.3.x and 2.0.x (both Unix and Windows).
XMB recommends using the latest version of Apache 2.0, suitably hardened and tuned for running forum software. Luckily, this is the web server of choice for most web hosts. If you have any queries about web server configuration, ask your web host for further information.
PHP
To install XMB 1.9.11, PHP version 4.3.0 is required, but the latest version is recommended.
Versions of PHP prior to 4.3.4 are essentially insecure and NOT recommended. Future versions of XMB may not support versions of PHP earlier than 4.3.4.
XMB fully supports PHP 5. PHP 5 is known to be faster and more secure. If you are running a busy forum, it is recommended that you use PHP 5.0 or later. The use of a PHP acclerator is also recommended for those operating busy forums.
MySQL
To install XMB 1.9.11, MySQL version 4.1.7 is required, but the latest version is recommended.
XMB fully supports MySQL 5.
FTP Client
FTP (File Transfer Protocol) is the most common method of uploading files to servers.
There are several free FTP clients availible:

- FTP Commander 7.0
- Core FTP Lite
- FileZilla Open Source FTP / SFTP Client
- SmartFTP

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