Please help! I believe this all started after an update, but I'm not sure. I believe I am now running Sierra, but I can't get in to confirm... My MBP began running very slowly one day. I noticed all of the memory was being used and tried to restart the computer to figure out the problem. The restart took almost an entire day, and once my computer was booted, I could not do anything on it for it running so slowly. Since then (a few months ago), I have been able to accomplish nothing on it. Last night I decided to look into it because, you know, I kind of need a computer. I tried booting in safe mode, and it got stuck. I tried loading the disk utility, and I ran the first aid, but it went even slower after that. Resetting the PRAM did nothing but freeze. This morning I went and purchased more memory. I believed from what I saw on my computer that I had 2 GB of RAM, but when I went to replace it, there was actually 4 GB. I installed 8 GB, and I could not get past the gray screen with the startup bar on it. I tried to reset the PRAM, but currently the startup loading bar has been stuck! Please help! I can't just go buy a new computer because when I really think this is something with the update! I am so frustrated and don't know what else to do. My husband is of no help because he is admantly against Apple products, so I'm on my own. Current situation: start up is taking so long that the screen keeps going to sleep.