I have a gray screen

Hello spacelab2000,

After reviewing your post, it sounds like you get a gray screen when you turn on the computer. I would recommend that you read these articles, they may be helpful in troubleshooting your issue.

About the screens you see when your Mac starts up - Apple Support

OS X Yosemite: If you see a gray screen at startup

Thanks for using Apple Support Communities.
Have a nice day

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