Use your best judgement. There really is no easy answer as each case is
The most important thing to considered is the source. Did the item being
identified come from a trusted source? However even in this instance, malware
can overwrite files from a trusted source on your PC.
The product used to perform the scan from which the false positive was reported,
may provide more information on the item. Use this information to help decide
what your course of action should be.
Some products also provide further help through forums, support and sample