I still don't have a USB 3 cord that attaches my external hard drive to my new MBA but that shouldn't be the reason I'm stuck in "preparing backup". I used google to find a solution but found differing info. What is the best way to get this fixed for someone like me who is non-technical? I've backed the system once before I installed the newest update a few days ago and it took a long time to back up and I do remember seeing the 'preparing backup' on my computer for a while then too but the MBA eventually backed up. This is getting ridiculous as now I can't back up. Please help. Thank you for your advice.