I need to move the contents of an old account to a new account on my IMac

Hello FMATB,

Thanks for seeking help here in the Apple Support Communities. I will be happy to offer some options for you to get all your data from one account on your iMac, to the account you normally use on the same computer.

The easiest way since you already have all the data now on the same computer, just under two different accounts, is to locate and organize your iTunes Media folder in the unused account. This help article from Apple will help you make sure all your songs, playlists, play counts, and library is all consolidated and ready to move: Locate and organize your iTunes media files.

Once that is done, this help article has a few options, and it also offers pictures to help you move the library using an external hard drive or flash (thumb) drive. How to move your iTunes library to a new computer. Since the data is on the same computer, just under different accounts, I recommend checking "Part 3: Copy the iTunes backup to your new computer", but you can use the external hard drive or flash (thumb) drive method, or you can use the Shared folder located in the Finder, Macintosh HD, Users, Shared.

Either option will help you complete moving your music from the unused account, and putting it in your main account. Be aware, if you currently have music on your main account, this will ask to replace the folder, or place it with all your other data. If you replace the data, the only music and data you will have will be from the second account. If you add to it, when you open iTunes, you may still not see your music until you switch libraries. If you need to switch libraries, please check this help article: Open a different iTunes Library file or create a new one.

Thanks and have a great rest of your day.