One of our client want to built a website in php, but this website already done in asp and hosted at web.com for some time. he want to built again the site from php. so i am about to offer a cpanel package. but he want all the emails and accounts to be migrated from web.com to his new cpanel account with us. but no idea wehere to start.
If they offer IMAP on their server, you can use imapsync to transfer emails to your cPanel server ( http://wiki.zimbra.com/wiki/Guide_to_imapsync ). If they offer POP only, all the older emails should be downloaded to their local machines already. Adjust TTL to minimal and switch DNS records. After DNS records are propagated, do a final email download from old server OR use fetchmail on new server to import emails from old server ( http://www.howtoforge.com/debian_etch_fetchmail - read section 3.2 )