I cannot put ogg on my sansa fuze

As many people on this forum have pointed out, many tag issues can be fixed with MP3Tag. Just open your files and resave the tags. You don’t even need to modify the tags, unless you want to.

If that doesn’t solve your problem, try using check disk. Just make sure your Fuze is connected in MSC mode, which will cause your player to emulate a portable hard drive. You can do this by moving the switch to the “hold” position. Then, press and hold the << button, while connecting your Fuze to your PC. Do  NOT stop holding rhe << button until your computer connects to the device and makes that “du-dink” sound. You will notice that two new drives appear. One of them is your player, and the other is your player’s memory card. At this point I recommend running check disk on both drives (unless either your memory card is blank, or you have no card, then you can just do the internal memory, which should be the only drive with files on it).

Now, if you don’t know what check disk is, it’s basically a utility to make sure everything on your device has been stored “properly”. It took me a few minutes of searching, but I finally found a simple guide on another site that actually makes sense, and explains how to use check disk. and HERE it is. Just make sure to take note that right below the pretty demo pictures, there is a “next” button, showing the next step in the process. Also, on the first step, when it says, “right click on the hard drive”, you need to click on the mp3 player (or card), instead. Other than that, the process should be pretty straight-forward. Good luck.