MostHost Linux Shared Web Hosting accounts use AtMail by default, but you can easily change to another program if you so desire.  Making such a change is easy.

While logged into your Plesk 10.2 control panel, click on the navigation tab "Mail."

Now click on "Change Settings."

In the middle of the page, you'll see a box that says "Settings."  Using the pull down menu, select the webmail program you want to use.  Once you're happy with your selection, click on "Ok."

If you want a webmail program installed that is not currently available, simply open a ticket and we'll be happy to add it for you (Linux only.)