Android File Transfer continuously fails to copy files to the SD card over USB in Android Lollipop

Solution 1:

Try using SmartFinder for Android. It's on the App Store and it's free. Make sure you have USB debugging enabled before using SmartFinder though.

How to enable USB debugging?
Go to your smartphone's Settings -> About device -> Tap on the Build number until you get a message "You are now a developer!"
Go back to the main page of Settings ->Developer options -> make sure USB debugging is ticked.

Once you connect your phone for the first time, it'll install an app called SmartFinder (about 4 MB) on your phone. It won't have an icon, no need to launch it.

Then, simply find the .mp3 file under Music in SmartFinder, select it and tap Import.

If that doesn't work, then the file might be corrupt.