1. open scanner
2. at bottom of scanner there are two plastic films on either side of the bottom of scanner.
3. get some nail varnish remover(100% acetone)
4. apply to lens cleaner cloth (eye glass cloth cleaner)
5. apply acetone to cloth then wipe gently across the two plastic films on bottom of machine.
6. apply until no more dirt lifts off. allow to evaporate(dry)
7. calibrate machine
8. clean machine
9. problem should be fixed clear scans. it worked for me
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