I have a client who has installed the Operator software on their PC. It had been working but now when he pulls it up, it comes up with a error that says License error then a bunch of letters (I believe it is ffffffc) I have the license has ayone else seen this, and if so how did you resolve it?

This is common.

The TSP driver that OS Operator uses has lost connection with OS Link.

Make sure OS Link is connected to the system.
Then run the reconnect utility or restart the pc with operator