System Requirements
To run the latest version of Simple:Press Forum the following system requirements need to be met:
WordPress version 3.0 or newer.
You can check your WordPress version in your site ‘dashboard’.
It is displayed in the footer on the right hand side.
Note that WordPress 3.0 also replaces the older ‘MU’ having merged the two strands.
Php version 4.3 or newer including the GD graphics library.
You can check your php version with your host but it is unlikely to be any older than 4.3. Simple:Press Forum also runs without problem on php version 5 and above.
MySQL version 4.1.21 or newer.
You can check your MySQL version with your host or with a tool such as phpMyAdmin – usually available from your hosting control panel. Simple:Press Forum also runs without problem on MySQL version 5 and above.
WP Theme Requirements 
There are three major requirements of any WP theme.
Sadly many theme authors leave out. These are required for Simple:Press versions 4.3.1 and newer.
These are:
- A call to wp_head() in the header theme file
- A call to the_content() in the man display page theme file
- A call to wp_footer() in the footer theme file
If ANY of these calls are missing, Simple:Press will not display and/or function correctly.
For details on checking and adding these requirements to an incorrectly written theme please see this wiki article.
