my macbook pro does not detect external display anymore

Has anyone else tried this & had it work yet?

I hate to be the dumb one here, but still new at the Mac experience - which button is considered the "apple button" when macbook is shutdown?

Hey everybody,

Im having the same problem, it looks like many people have been experiencing this same problem and yet theres been no solution for THREE years?! -_-

Has anybody tried anything that works?

Thanks

Hi SMRosenthal,

Even though I had random sleep problems that have been since been fixed, I haven't had problem on external displays since April 2013 (techie speak: 2013-04-07). Back at that time, with the help of others, I gave a nerdy post that probably solved most people's problems.

Have you tried that?

Now I'm using Mavericks. I have not had a problem for about 1 year. To get to Mavericks, you might have to give $25 bucks to upgrade to Mountain Lion then you'll have a free upgrade to Mavericks. I know I don't like to give cash but economically, with the time you're spending on forums finding a solution, you'll prolly pay it off upgrading and working on your product, education or in your industry instead.

The upgrade to Mavericks has been easy... just don't force restart your computer during the upgrade even if you've think it has been too long or you'll have a paperweight.

Honestly, it would be nice if Apple would respond with a definite answer. Apple prolly has so many forums to monitor and honestly, even if there are some gems of advice, I don't want Apple to start carelessly pushing offshored MVPs like MS has in their forums. We have to help ourselves fix it when there is unfortunate silence.

Thanks for the speedy reply.

I havnt seen your other post but i have the white curved macbook, not too old, previous version from macbook pro, and its 10.8.6. Is there another solution? Like a step by step instruction?

Well i now have Mavericks 10.9.2 amd still nothing. Instead of a quick blue screen, its now a quick black screen then nothing :[

it worked for me. Many thanks. I thought i damaged my minidisplayport. thanks again.

I have tried everything described in this topic. Nothing worked for me. When I am at home and connect the laptop with my TV there is signal. When I am at office trying to connect it with my DELL U2713H it says there is nothing to dectect and that my laptop has stopped giving signals. Two months before there was no problem working and watching movies on both displays. 😟

Specs:

MacBook Pro, 17-inch, Early 2009

Processor 2.66 GHz Intel Core 2 Duo

Graphics NVIDIA GeForce 9600M GT 512 MB

Help!

I am having the same problem. Why can't apple fix this!

I used my Macbook Pro to project to my home TV and a projector at church for months. Then all of a sudden, it quit. I brought my computer and cables into the Apple store and connected to their TV, and everything worked. Then I went home, and I was back to the same problem.

I went back to the Apple store and purchased a new lightning to HDMI cable (shelled out another $40) just to try something different, and it stated working again. A few months later, it stopped working again, for both my TV and the projector at church.

When I go to Displays, I can no longer see the block that allows me to check wether I want to turn on or off mirroring.

Can anyone help?

Hi all.

Same problem here as everyone else. I have been using a Samsung Syncmaster 22" VGA monitor as 2nd display, but last night while my macbook retina early 2013 model was in sleep mode, I closed the lit and I did notice the external monitor flicker for a split second and then go back to being black.

After that my macbook is not detecting it anymore. I don't have the "Arrangement" tab in my Display preferences. It does however work perfect if I connect to my philips TV with HDMI.

I have tried all the tricks mentioned in this year long post, so tomorrow I'll visit the local apple store and bring my VGA adapter to see if it fails with other screens and other macbooks at the apple store as well. If it does, I will buy a new adapter.

open disk utility and then run "verify disk permissions" and "repair disk permissions". It may can help.

Thank you very much austhehaus22 and SanctionOne; SanctionOne's solution worked for me. Much appreciated.

After two years of battling with the positioning of my cables and adapter to get a consistent display free of intereference or just to plain work and not get the NO SIGNAL message (and I do think it's a electrical interference problem with crap quality protection within the adapater) I purchased this - a single cable, no adapter, with a nice and thick protective sheathing and BANG! works perfectly fiirst time, not a glitch and also the response rate of the interface is even faster. Go try it, if it doesn't work you can always return it.

No help. 😟

wow. wow. wow. really??

Suffering from the same problem here. the Command + Option + P + R worked only the first time. Now it's random, sometimes it works (5% of the time), and then it does not. I cannot figure out what makes it work.

Steve Jobs would have had a few people executed already. Apple's going down...

I had this problem too, but found the solution, thanks to sn_.

Basically, my MBP has two graphics cards, an onboard "Integrated" Intel HD4000 graphics card, and a "Discrete" nvidia graphics card. The "Energy Saver" preferences panel has a setting for "Automatic graphics switching", which automatically switches to the nvidia card when I connect external monitors, and to the onboard card when disconnecting them.

The problem apparently started after I installed gfxCardStatus (for a completely unrelated issue) and selected the "Integrated Only" option. This didn't untoggle the "Automatic graphics switching" option, but had the same effect of preventing the MBP from selecting the nvidia card when I connected the external displays.

So the solution for me was pretty simple: on the gfxCardStatus menu, I selected "Discrete Only" after connecting the external displays, and it worked right away. I could probably have also selected "Dynamic Switching", but didn't feel like experimenting with it right now. I'm guessing another option is to actually get rid of gfxCardStatus and revert to the built-in MBP settings.