ResolutionIf you want to use the commercial version of AtMail on your Parallels Plesk Panel server, follow the instruction on the official Atmail site:
Plesk 10 support now available in Atmail Webmail
Additional information1. According to Atmail System Requirements, Parallels Plesk Panel for Windows is not currently supported. (Atmail is making efforts to support Plesk Panel for Windows in the future).
2. If Atmail supports parallels Plesk Panel for Windows in the future, users with APS on Windows 2008 / Windows 2008 R2 must add web.config in %plesk_dir%\admin\htdocs directory with the following content:
<?xml version="1.0" encoding="utf-8" ?>
<requestLimits maxAllowedContentLength="50000000" />
After the directory is added, the Parallels Plesk Panel service must be restarted.