We recently migrated over to Redhat 9 (2 months ago. All was running well until 2 days ago (maybe longer but we don't know). Email exist in User Mailbox but some of them cannot be retrieved to be read at client. One person could not receive "some" email received. I check the User Mailbox and saw he had 5 unread email (internal and external email). But he was unable to retrieve them. Tested my email account and could receive all email. Checked his Outlookconfig, all looked fine. Another client called this morning with same problem: some email were unretrievable. Tested both accounts with yahoo, hotmail and excite email...they receive those. Tested from two internal accounts with and without attachments...some were retrieved (attachments and no attachments). Please assist...the clients are getting frustrated at me.

could you explain your problem properly? What are you using to read your mail? Sendmail is an MTA, it its job is to send and recieve email directly to/from your computer. (so you don't use somebody else's pop/smtp mail server). Are you using mutt to read your email? are you using Ximian Evolution? Mozilla Mail?