It is possible and can happen depending on the file structure set by the OS. It can be different depending on a number of factors. Mainframes and mid range computer had blocking factors for the files. Never checked this out but if one file has a lot of deleted records I don’t know if the FTP only sends active records. If the systems are running different OS that would be my first guess. Provide some additional info and we can try and help straighten this out. Also just to make sure you have all the data, check out the record count on both systems to make sure all the data did copy over correctly.