iTunes Back up corrupt

After updating my 6s from 9.2 to 9.2.1, every time I try to backup to iCloud or my computer, I get a message that says, "iTunes could not back up the iPhone 6s because the backup was corrupt or not compatible with the iPhone." "Delete the backup for this iPhone, then try again.'

So I deleted the iCloud backup and tried again and received the same message. Any clues?

The only troubleshooting I've done is to restart my iMac. Not sure what else to do.

Late 2013 27" iMac

Yosemite 10.10.5

32 GB Memory

3 TB Hard Drive with 1.8 TB available.

iPhone 6s running iOS 9.2.1