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Power down you machine and remove everything from your controller except power, machine communication, and the monitor.
Power back up.
Does the controller boot farther into PathPilot?
If yes, attach one USB at a time until you find the problematic USB connection.
If no, check time and date in BIOS. power down controller and restart (to get into bios, see below)
To get into BIOS, restart computer and rapidly press F2 or F10 (tower controllers), or Del (for brix, rev c, rev d etc.) . or F2 or F10 (tower controllers), If your date and time are accurate, and you still are having issues, restore to factory settings.
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