Huge grey question marks on the Mac Dock

marimoc wrote:

Hey I just bought a MacBook Pro A1278 Core i5 2nd hand online, first experience with Mac products. None of the functions seems to be working. System preferences no, App Store no, Applications no. I googled for troubleshooting and got something like force quitting and opening in safe mode. I tried it and now no app icons on the dock, just huge grey question marks.

Still no functions working. I can't open system preferences I can't open system update, applications nothing.

Please assist

[Re-Titled by Moderator]

I would consider returning the 2nd hand Mac.... for one than works as expected.

ref

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