Please check the following points according to your preferred paper feed method:
[For the U-turn path]
- Is the center of the loaded document aligned with the center of the extension (document holder)
(in the figure below)?
- Are the side guides (
in the figure below) of the ADF paper chute (cover) aligned with both edges of the loaded document perfectly?
- Is the loaded document one of the following?
・Thin paper (less than 40 g/㎡ (as thin as a receipt))
・Torn paper
・Non-rectangular paper such as newspaper clippings
・Perforated paper
・Wrinkled or curled paper
*If the document is one of the above, place the document in an optional Carrier Sheet and perform a scan using the return path instead of the U-turn path.
[For the return path]
Did you insert the end of the document straight into and parallel to the manual feeder ( 
in the figure below)?
*If you inserted the document at an angle and want to load it again, you can pull the ADF release tab (
in the figure below) toward you to open the ADF top section, pull out the document, and then load it again.
*If you inserted the document at an angle and want to load it again, you can pull the ADF release tab (
If the problem still persists, refer to the following topic in the ScanSnap Help, take the measures described, and see if the problem is resolved.
"The Document Is Not Fed Smoothly/A Paper Jam Occurs"