The problem is with me email client IncrediMail Xe

Hi,
The problem is with me email client IncrediMail Xe. It was running well.
However, at present it is showing the message as under. I am trying to solve it but no result.
If you have any idea please help.

IncrediMail Xe
One or more message could not be sent.
These messages are still in your Outbox, please correct them and then try again.
