hi. there is a qmail server running in the office. we are using 2 Mb/s dedicated connection with web server along with the ajax based
mail server. we are hearing complains from various users inspite of the fact that the mail server is working fine about MUA's(mail user agents) taking too much time to download the mail.Nowadays there are attachments in most of the mails. the mails in Mb/s mostly take time to download. Now I and my coworkers are thinking of enhancing the bandwidth, but one piece of advice i would like to take from the people here is that if there is any chance that the problem can be from the mail server, where can be the problem and how to end that problem. Is there any way to solve this problem staying on the same bandwidth.

More bandwidth always helps. You don't detail your server, and a morning rush of everyone getting the mail that was sent out last night is often a very busy time. Is spamassassin or friends, clamav or friends, lookup services (e.g. Vipul's pazor, spamhaus lists) or procmail involved? Procmail can be very heavy on memory

I would observe top and free outputs tomorrow morning, or whenever is the busiest time for you. qmail should be quick, and fast.