Lane 1, lap rejected because 0 < 1

I have just set up a track after 11 months of non use. I have PC Lapcounter 5.36c.
The last time I used the C7042 and PCLC, I had no problems.

Now, when a car crosses the line, the car is detected, but the software thinks the lap time is 0.
So the message occurs:
Lane X, lap rejected because 0 < 1
(X can be any lane, they are all the same)

I have tried the setting which gets the time from the C7042, turned on and off, it makes no difference.

Any ideas?

I rebooted the laptop and all is now OK.
I reset the C7042 several times, but hadn't thought to reset the laptop!