Please find the extractor.exe file on the system and then go to the path using CMD, once you have reached to the location, use the below command.
Extractor.exe -F Sourcepath\filename.BAK -E Destinationpath\filename_native.bak
If you don't have extractor.exe then copy the same from any server to the destination server and then try to extract it.
Extractor.exe -F Sourcepath\filename.BAK -E Destinationpath\filename_native.bak
If you don't have extractor.exe then copy the same from any server to the destination server and then try to extract it.