There are several things that can cause a paper jam error, even though there is no paper stuck. The most common is that the paper pickup rollers are worn or dirty, and can't grab paper. Even though there is no paper jammed in the machine, it will show the error message. The solution is to clean the roller with alcohol and a lint-free cloth (don't use paper towels). If the roller is very worn, you will need to replace it.
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