H-Sphere supports two webmail clients: SqWebMail (the default) written in C and IMP WebMail written in PHP (see enabling IMP).
SqWebMail is a web CGI client for sending and receiving E-mail using Maildir mailboxes. SqWebMail DOES NOT support traditional Mailbox files, only Maildirs.

Location of files

1. for qmail

/hsphere/local/var/qmail/bin - binary executable files
/hsphere/local/var/qmail/boot - different variants of startup files (not recommended to change!)
/hsphere/local/var/qmail/configure - binary files used for installation and configuration
/hsphere/local/var/qmail/control - configuration files
/hsphere/local/var/qmail/man - manuals for qmail
/hsphere/local/var/qmail/queue - the sequence for letters to be placed before delivery
/hsphere/local/var/qmail/users - plain-text databases with all mail clients

2. for vpopmail

   ~vpopmail/bin - binary executable files
   ~vpopmail/doc - documentation
   ~vpopmail/domains - directory comprising all mail domains registered in the system, their POP boxes, etc.
   ~vpopmail/etc - files with TCP environments required for POP3 server operation
   ~vpopmail/include - system service files
   ~vpopmail/lib - libraries of the program
   ~vpopmail/users - not used in H--Sphere