Need Help with build

I recently got someone to help me make a simple game. They are no longer helping me out, but I figured out some of it by myself. I’m now trying to finish it and build it. But when I build it I get this error.

Error building Player: IOException: Temp\StagingArea\plugins\android-support-v4.jar already exists

Can anyone figure this out?

Well this is quite beyond my skill level, but if it was me I would navigate to Temp\StagingArea\plugins\android-support-v4.jar, and delete android-support-v4.jar (back it up in a safe place first), and retry build. If it does not work, just put the file back, and your back were you started. Again I don’t know, so you might want to wait for a better answer.