ATPmail Pro

If you haven't looked lately, take another look. ATPmail Pro has been completely redesigned. Email, calendar, tasks, files, address book, filters, white list, everything. DHTML makes it feel like a desktop app. Try the demo, no signup. Easy installation. Available for single or multi-users. 100% standard Perl, even runs on Windows with apache or IIS. ATPmail is a Web-based email program that will turn any POP email account into Webmail. Features: Easy installation, Powerful admin tools, Individual user quotas, User migration, Supports both Sendmail and SMTP, Alter appearance, Efficient, frame-based interface, Multiple email accounts, Address book, Mail folders, Search messages, Mail filters, Webdrive, Attachment support, and more.