Is a document jammed inside the ScanSnap?
Remove the jammed document, and perform scanning again.
For details, refer to Removing a jammed document.
Is the ADF top section open?
Remove the document that you are scanning, and close the ADF top section .
Close the ADF top section together with the stacker until it locks into position, indicated by a clicking sound.
If none of the above is applicable, close the ADF paper chute (cover) of the ScanSnap to turn it off, and then leave it for at least 5 seconds. Or, if the ADF paper chute (cover) is already closed, open the ADF paper chute (cover) and close it again to turn it off, and then leave it for at least 5 seconds.
After that, open the ADF paper chute (cover) or press the [Scan] button to turn the power on, and then perform scanning again.