Its a known fact, that OSX can not write HFS Standard floppies as of 10.6 and higher. However there is the dd command available in all *nix systems. Unix guys will know. For the others, dd and Terminal can do many useful things, including writing HFS floppies. What is needed: Mac OSX 10.12 or lower. Termial App from Application/Utilities USB floppy drive. Installation of MiniVmac_II with Mac OS 7.5 RAW floppy image Transport dmg, DOS formatted. The last three are included in the DL file. Lets assume you want to write the game file Mac Yahtzee to floppy with you Mac running Sierra. http://macintoshgarden.org/games/mac-yahtzee Its impossible to write to a HFS Standard volume from userland. We may write to DOS volumes though and MacOS 7.5 does read those volumes too. Double click the Transport.dmg and copy the downloaded mac_yahtzee.sit to it. Drag Transport.dmg into your Sierra dustbin when done. Double click Mini Mac 2673.app and drag MacII_HD75 onto it as the screen with the blinking question mark appears. Next drag Transport.dmg onto Mini Mac´s screen to mount it. Open Transport.dmg, copy the sit file to the TEMP folder and drag and drop the sit onto the Stuffit Expander alias. Unmout Transport.dmg by dragging it into the Mini VMac dustbin when done. Copy the 1440.dsk file from the DL to the root directory of your boot volume. Your user pass will be needed to do so with Sierra. The dd command seems to be picky when writing files to floppy, so you do use the untouched 1440 RAW image from the DL. Drag the 1440.dsk onto the Mini VMac screen and copy the MacYahtzee app to it. Shut down Mini Mac when you are done. Insert a floppy and open DiskUtility. Use the Info button to find out the device ID of your floppy. For this example, lets assume the floppy is disk3. Now select Unmount. Open Terminal and type in (or copy/paste): Code: sudo dd if=/1440.dsk of=/dev/disk3 Because of sudo, you will have to type in your OSX password. The copy process will need some time. The whole floppy is written. As you got a similar output as the above picture, use DiskUtility to mount/ unmount to see it in Finder. Done. Your files should show up on floppy! Now eject 1440 and take it to your vintage Mac. Have fun! Many thanks to all those tinkering with dd, especially to Max1zzz for pointing to RAW and MiniVMac! At last a warning to the casual reader: Though very little can go wrong, if you follow the above to the letter, it is jokingly said that dd stands for "destroy disk" or "delete data", since when used for low-level operations on hard disks, a small mistake such as reversing the input file and output file parameters could result in the loss of some or all data on a disk. m http://en.wikipedia.org/wiki/Dd_(Unix m ) Edit: I don't have a suitable Mac any more to read the floppy created above. Basilisk II build 142 for Windows does read HFS floppies though, this is how it looks: