5 Replies Latest reply: Oct 16, 2012 10:30 AM by Number34
Lolipo Level 1 Level 1

I just updated my MacBook Pro (Late 2011) and the new OS 10.7.5 is not recognizing my second display (VGA connected emachines 19''). I have restarted, changed the resolution, and tried many things, but the display that was working perfectly two hours ago now does not work. Help pls

MacBook Pro, Mac OS X (10.7.5)
  • absenter Level 1 Level 1

    I am having this same issue.  Second monitor just blinks occasionally.  Worked fine just before the update.

  • Number34 Level 1 Level 1

    Same here.  After I updated yesterday I no longer have the option to rotate my 2nd display 90 degrees in Display Prefs.  It's getting a signal and I can change the resolution to it but don't have the option to rotate the image to fit the orientation of the monitor.  Hope this doesn't mean I have to wait until the next update.


    MBP2.2 i7, OSX 10.7.5

  • Lolipo Level 1 Level 1

    Ok I solved it.


    This worked for me:


    First, I got gfxCardStatus v2.3 (as adviced here https://discussions.apple.com/message/18028302#18028302)


    however, this does not solve the problem right away, it is only the first step. After dwld gfxCardStatus I plugged the second display (using dvi adaptor) and my laptop's screen kept turning blue then back to normal, then blue again. IN the meantime secondray display was not recognized. I just let it go crazy for a while, and it eventually stopped blinking into blue (at this point it did not recognized the connected display, though). 


    So, once the system is stabilized (stopped blinking into blue), I placed gfxCardStatus on "discrete only" and went to "system preferences>Display preferences>gather windows" I was then able to change the settings for the secondary monitor, I tried virtually all the setting, the only one that worked for me was a thighest resolution at 60hz.


    Now the monitor is working, it blinks now and then, and it is not the most stable arrangement, but I allows me to keep the harware I now have...


    what a nasty, time consuming update this was...

  • emgsilva Level 1 Level 1

    Hi There,


    I suggested the solution on the link you refer (to solve this type of problem with gfxCardStatus)... unfortunately this solution did not solve the problem when upgrading to the 10.7.5, namely the new "supplemental update" that was released on the 4th of October (http://support.apple.com/kb/DL1599).


    Here is a simple procedure I followed and solved the problem for me... this worked by chance after starting following the instructions in: https://discussions.apple.com/message/19979833#19979833.


    1. Restart your machine and, when the machine is in booting press "alt" (left option) to show a booting menu.
    2. Select "recovery mode" (do this with the external display connected)
    3. In the recovery mode you can test if the external display is detected (it should work normally)
    4. Do not do anything in the recovery mode... simply Restart you machine (now in normal mode)
    5. It should work normally now... (at least it worked for me)


    I think this has to do with a kind of "reset" on the external displays configurations... But I still do not fully understand why this happened.


    I hope this helps some people! Cheers!

  • Number34 Level 1 Level 1



    Thank you so much for the reply.  This procedure worked beautifully and I am now up and running a 2nd monitor for the 1st time since the upgrade.  Never heard of recovery mode before and I'm not exactly sure what happened, but it worked.