You attempt to send a fax using Winfax Pro and it no longer functions or when opening Winfax Pro directly it just freezes up.
This usually indicates that the Winfax Pro data folder has corruption. You can browse to C:Program Files\Winfax\ and rename the "Data" folder and then open Winfax Pro. This will create a new "Data" folder and will also remove all archived logs such as the "Sent" or "Deleted" etc. This should correct the issue and Winfax Pro should start working again.