Need Help - Gone from bad to worse
 

I posted about not being able to add an app.

Now, the iPod has lost (?) all but the defaults. I can see all the apps that should be loaded in C:\Users\[user]\My Music\iTunes\iTunes Media\Mobile Applications\ as .ipa files.

Numerous attempts to sync (via USB cable or Wi-Fi) achieve absolutely nothing.

Any suggestions? Thanks

You could use iExplorer to put all the apps onto your iPod. Then go on your iPod and install from there using a file viewer.
Good luck.