Hello, I am sorry if this has been addressed before, but I kept finding the topic from previous OSes before Sierra. With that being said, I came home this afternoon and powered on my iMac like normal. I tried opening up Safari, but as soon as I clicked on it, the app put up the normal "Program Quit Unexpectedly" error. So I went onto Firefox and found a solution that helped me fix that. Now I tried opening up Mail, and mail started giving me the same "Program Quit Unexpectedly" error. Starting to get frustrated, I opened up the App Store to see if there were possible updates and I do have four that need to be done, but I still get the "Program Quit Unexpectedly" error when trying to Install the updates. So with no other idea that might be able to fix this, I decided to download the Sierra update again from the Apple website. When I try to get the install to go, it gives me "Program Quit Unexpectedly" error. I am out of ideas and I am hoping that perhaps someone with more technical experience could help me figure out what could be the problem. I couldn't see any malware from some YouTube videos I watched, but maybe there is something new out there that someone might be aware of? Please help, Thank you!