no device found on com7

I am busy on a project with the DUE. It has worked (partly), but now the download results in: No device found on COM7.
Compiling goes well, the board is mentioned as the DUE,
Tools: Board says: Arduino Due (programming port)
port: COM7:(Arduino Due programming port)
But trying to load the program to the board: No device found on Com7
Can anybody explain this?
System is Windows10 on a HP laptop. But again, it has worked.


Those problems are frequent (remember: computing is not an exact science; the newer the system the lesser the reliability)

Try disabling re-enabling the port while reseting the board (and viceversa). if it doesn't work just switch them (computer and board) off then on.

Best regards