The iPod shows “0 songs”
After copying music by hand, the iPod may not show it because its iTunesDB database does not list those tracks.
Common causes
Files in unsupported formats (FLAC, WMA, OGG), an iTunesDB that does not match the files, or an interrupted copy.
How to fix it
Remove the unsupported files and sync again: iPod WebSync rewrites the iTunesDB with the master song list. With a pass there is also an iPod rescue and repair tool.
Sync your iPod from the browser, nothing to install.
Open iPod WebSync