Hi, can anybody help with a problem on my xn900 checkout till.
On starting the till when the soft where is running an error message comes up
saying invalid dongle ok,error with device connected to port 1 ok,
then the till restarts and i have to start the software again then the problem
happens again. Any help would be great thanks.

in the back of the machine, in the parallel port, therew should be a licence dongle.
If so, remove then refit it. These had a tendency to "go missing" when the xn was powered up.
You may have a more modern - usb dongle. this has never caused me an issue unless the licence code in the software does not match the code in the dongle [code is held in the network.buf file]
Or perhaps you just dont have a dongle plugged in at all?

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