Whilst both .gp5 and .gp3 files originate from Guitar Pro program, it it doesn't seem possibly to just resave one to another using the program or any other similar music software. That is because Guitar Pro formats lacks backward compatibility.
This conversion entry was verified by us and conversion was flagged as wrong or not possible.
Usually this happens when the conversion would try to convert different types of data between each other, such as audio to image, or it is not possible because incompatibility between programs, caused by closed file formats, very limited support etc.
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