Client receiving duplicate emails

My most troublesome client is now complaining that she is receiving duplicate emails. Of course, not consistently, and not always from the same sender. Also, she is the only one in her office that is having this problem; there has been no mention that any of her coworkers are having the same problem.

My question is this: have there been any problems on the email servers that could account for this? My best guess is that her email client is starting a download, not deleting the message from the server for some reason, then downloading it a second time. This client tends to send and receive messages with large attachments, so I’m thinking that time-outs might be a problem here.

Any information you could give me would be extremely helpful.

This(duplicate email) might be possible due to mail client configuration. Please ask her to configure mail client again. If the issue will be continue then please provide us the complete email header in ticket which she received two times. We will check it and update you back as soon as possible.