I have a customer that is getting the error message pop lock busy. I use a program in dos called xtelnet to check his mail. Sometimes I get the same thing. Sometimes I get through. His e-mail is stopping at the 4th one when there are 16 e-mails on the server. I think one of the e-mails is too large for Outlook Express to handle. The e-mail is 534381k. Is this too large for Outlook Express to handle. I have also heard that when e-mail does not come through the e-mail could be in the wrong format. Is this true and is there any way to check what format the e-mail is in? Thanks for your help.