Hi, this printer is keeping saying that there document jam when trying to scan - possibly in ADF and my customer said, that she scan only from ADF and not from the scanner lid. There was some paper jam before, which I see it was cleared. I didn't disassemble anything. BTW, now I see I can't scan from ADF through the SmartThru Scan Utility - says there is paper jam in ADF. What might be the cause? Thank you.