The simplest way is to log in to your SiteMadeEasy Web Control Panel (http://yourdomain.com/cgi-bin/plusmail), it is displayed on the main screen.
You also can log into your domain using a secure telnet program and type:
If you want a disk space usage broken down by directory, run "du -hL" from the telnet command line.
If you're out of space, order more disk space here.
There is also an extensive online manual available.
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