USB transfer was successful once then USB lost memory campacity

Itunes... connect iPod to computer and clik on iTunes and then follow on screen directions to sync iPod...

Connect both using a USB cable a display will show on your I phone4 screen with different options. Click the one permitting the PC to read it's storage.
From here your phone's storage is shared with the PC it will indicate on your pc and you can now do your transfer then unplog.

Follow the link for instructions How to Download Songs Onto an iPod Shuffle

If you'a an iPhone user, you can use iTunes to transfer music from iPhone to computer first. You may have well known that iTunes only transfers purchased items from iPhone to iTunes library, so iPhone users can move purchased songs from iPhone to iTunes library.

1. Run iTunes and click "Edit > Preferences > Device > Prevent iPhones, iPods and iPads from syncing automatically" at the upper left corner of iTunes window.
2. Plug iPhone into computer via the USB cable, and then click "File > Device > Transfer Purchases" at the upper left corner.
3. iTunes will start to sync all the purchased items back to its library.

After the syncing process, you will get the music files in your iTunes library, including the purchased music files. You are able to find the music files in the folder of your iTunes media files on your computer.

The next step is really easy. Since the music you want is already saved on your computer, you can now simply connect your MP3 player, drag and drop to transfer songs.

On the contrary, here's also a guide about Three Ways to Transfer MP3 Files to iPhone in case you need help.

Sorry for my silly question but what is hot men? Is it a song you want?

If the song is already on your computer and you want to transfer it to your iPod, you can always count on iTunes.

The next guidance will show you how to transfer music from computer to iPod with iTunes.

1. Connect your iPod to PC via matched USB cable. Then click the iPod icon on the left corner of the interface. To manage your media files manually, you'd better go to "Options" under "Summary" tab, cancel "Automatically sync when this iPod is connected" and check "Manually manage music and videos". Don't forget to click "Apply" when it's done.
2. Import music into iTunes library from computer by clicking "File" and then "Add File to Library". Once transferred successfully, you can select the music icon on top to see all the songs.
3. Click "Music" under "Settings" tab. Choose "Sync Music". You can either sync entire music library or selected playlists as you like. Then click "Sync" button at the bottom to transfer music from computer to iPod.

If you don't want to use iTunes, please take a look at this guide for an alternative method.
http://www.leawo.org/tutorial/how-to-transfer-music-to-ipod-without-itunes.html

iTunes is always the first choice for most of iPod users when it comes to transferring music from computer. It can help you transfer and backup files easily.

1. Connect your iPod to PC via matched USB cable.
2. Click the phone icon on the left corner of the interface. To manage your media files manually, you'd better go to "Options" under "Summary"tab, cancel "Automatically sync when this iPhone is connected" and check "Manually manage music and videos". Don't forget to click "Apply" when it's done.
3. Import music into iTunes library from computer by clicking "File" and then "Add File to Library". Once transferred successfully, you can select the music icon on top to see all the songs.
4. Click "Music" under "Settings" tab. Choose "Sync Music". You can either sync entire music library or selected playlists as you like. Then click "Sync" button at the bottom.

http://www.leawo.org/tutorial/transfer-music-to-iphone.html

Assuming you have iTunes installed....

Connect iPod, when iTunes opens, you can go to File ---> Add File to Library (or press Ctrl+O), find the music file on your harddrive, highlight, and click ok. You can then manage the id3 tags (Genre, Artist, etc) by right-clicking on the song, and selecting "Get Info"

Hope this helps!

-- RT

PS - Don't forget to vote!