key found ,but license file not found ,why?
Probably because you don't have one. If you have a key then there is no need for a license file. Only one of the two is required.
I'm not sure what you mean by "error display". The message you posted looks like message sent on the event port to indicate that C-Gate is performing a check for a license. I'm pretty sure this is a normal message and is covered in the documentation ( http://www2.clipsal.com/cis/technical/downloads/developer_tools#Cgatedoco ), although not a great deal of information is in there on that specific message. However, it does cover the real licensing errors should you ever get one. ( Reference|Command and Monitoring Interfaces|Event Interface|Event Table|Licensing Errors )
