I have similar error.
I have a new computer running windows 8 I have been installing my web assist tools as I have needed them. I tried to install "Digital File Pro" but I got an error "activation cannot be completed." usually this error can be fixed by using a separate serial number but in this case there is only one, so I can't activate it. I have tried resetting activations and this has not worked, any help in this matter would be gratefully received.