Model A1312 / Mid 2011 / 2.7 & 3.1 GHz Core i5 or 3.4 GHz Core i7 Processor, ID iMac12,2

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Display doing odd things

My 27" iMac with El Capitan OSX10.11.4 displayed flickering white screen, blue screen, then solid white after downloading Adobe Flash Player from CNN News (I download Flash in order to play a news video.)

When I restarted, the iMac would display the Apple for a short while, then startup would stop, and it would show a vertical green stripes over the white screen. Or sometimes a blue screen then a static white screen

I spent 2 days reading tech threads trying to diagnose the problem (had no idea what caused it at first.) I could boot the iMac after resetting SMC and PRAM, everything seemed fine again, but seems any video I played would cause the iMac to crash (a flickering white screen, then solid blue, then solid white.) So, I suggest you disable Wi-Fi while completing the following fix, use a separate computer for internet research.

To boot/access my iMac I followed, in order, these standard Apple steps:

Reset SMC:

Unplug both ends of power cord. Unplug any peripherals. Wait 1 minute. Plug in power cord and restart.

Reset PRAM:

Start Mac, hold Command, Option, and P and R Keys until Apple appears. Restart.

Safe Mode Boot:

Start Mac, Hold Command and R keys after chime and until apple shows up. Then proceed to Disc Utility and run First Aid.

On a separate computer, I found the incredibly helpful thread (link below) and downloaded the Adobe Flash uninstaller to a thumb-drive. I uninstalled the Flash Player from the iMac.

I downloaded (to a thumb drive) the official Flash Player version from Adobe, installed it on my iMac. The flashing and blue-then-white screen problem have completely disappeared.]

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For years we never had to worry about viruses on Macs. Now, almost every one that comes in has them. I usually suggest Symantec (Norton). I think after Apple got so big they became a target. Anyway this will pick up those nasty installs that look safe. I never download updates except from the original site as they stick other things in or make it very difficult to spot other things they attach. Never call a phone number if an error pops up that is given, always look the number up yourself. The Phishing sites lock you up and give you a number to call to fix it so they can steal your information, get you to install remote access then ransom it back to you. Never install anything to clean up your Mac or manage it. Things like MacKeeper (see the class action law suit that was out on them), or Clean my Mac. Never believe that Microsoft is calling you or the IRS, FBI, CIA or NSA they are all scams, look up the phone numbers you are given. It's a nasty world out there and scammers are working 24/7.

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even Symantec can be nasty if you don't keep it valid , if you let it laps and don't renew it it will lock you out of your nic so you cant get on the web" they want you to be safe you know"


@jimfixer - send me a personal email on this.


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