I have recently solved a problem I had with my iPod, that started suddenly without any appearent cause. The issue was that every time I connected the iPod to the computer, as soon as it was detected and the iPod appeared in iTunes, iTunes would crash and close.
So basicly the iPod worked but it was impossible to use it with iTunes, therefore impossible to update or change the content.
I tried installing several different versions of iTunes in different computers but I always had the same problem.
Finally I came to a solution that worked for me:
I connected the iPod to the computer but I didn't use iTunes. I accessed it via the file explorer.
To see the music folders you need to activate the optino "Show hidden folders" [1]. Then you navigate to your iPod and you should see a folder called "iPod_Control" and inside it a folder called "Music". If you navigate into this folder you will see several folders with coded names and inside all your mp3 music files with, again, coded names (combinations of four letters).
So what I did was to "Cut" all these folders containing all my music, and move it to the hard drive of my computer.
When the iPod was empty of music (in fact, it worked without even removing all the music), I tried iTunes and it worked: I could access again (my now empty) iPod through iTunes.
Then I made an "Update and restore" of the iPod through iTunes.
How to put back the music into the iPod. As you may have guessed, you have only to drag and drop all the music folders (the ones with coded names) that you have copied into your computer's hard-drive to your iPod using iTunes. You will see the music will appear again (with it's properties), and you will have again a fully operational iPod.
You will have "only" lost your playlists.
[1] In Windows 7, I did it by pressing "Alt" in the file explorer. A bar with extra options appear on the top. You can also try this:
https://support.microsoft.com/en-us/help/14201/windows-show-hidden-files
