How to access an iMac which is still locked to previous owner?
I purchased a used 2017 iMac The previous owner stated that she reset the computer and all I had to do was set up with my new info. Well, I turned on the comp and I got a pic of a folder with a question mark. I googled what I could do from here and I read that I should shut my comp down then restart while holding the command and R key. This time I was able to set up my wifi and after doing so a picture of a world popped up. From here, I could not do anything! I can not get access to any computer folders or Apple menu. NEED HELP/ ADVICE PLEASE
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