Although both .flka and .flk files originate from Folder Lock and are used for encrypted files or archives, it doesn't seem possible to convert one to another. At best you could decrypt the files and get the original contents back and then encrypt again with a different function, but that's hardly a conversion.
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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