Just installed update, Mac won't load

Discussion in 'Mac Basics and Help' started by bubzbubby, May 27, 2010.

  1. bubzbubby macrumors newbie

    May 27, 2010
    I have a MacBook and I just installed a software update a couple of days ago. After the update my Mac boots, you see the logo and when it tries to load in home screen is when it does not fully load and my screen is chopped and scrambled all over. I don't know what to do. Can someone please help me? Thank You!
  2. bmcgonag macrumors 65816


    Mar 20, 2007
    Try resetting the PRAM. to do this. reboot your mac, or start it up, and at the boing hold down Option+Command+P+R (all at the same time) until it reboots again on it's own and you hear the boing sound again.

    Then let it boot up and see if it's better.
  3. bubzbubby thread starter macrumors newbie

    May 27, 2010
    Thanks for the tips however I tried to do it a few times and nothing seems to have happened.
  4. calderone macrumors 68040


    Aug 28, 2009
    When you say "home screen" do you mean your Desktop?

    Try Safe Boot, turn on the Mac and hold Shift.

    If it boots normally, we can narrow down the problem.
  5. bubzbubby thread starter macrumors newbie

    May 27, 2010

    Ok it is loading in safe mode and my desktop is normal. Thank you! What went wrong and what can I do to fix it?
  6. calderone macrumors 68040


    Aug 28, 2009
    To find out what is causing it will take a little work. Given the point of failure is when your Desktop is loading, that leads me to think that something being launched by your launchd process is causing it. To be sure, I need you to try a few more things.

    If you haven't already, confirm the problem still exists after booting into safe mode. While unlikely, given the point of failure, the removal of the various boot caches may have fixed the problem.

    If the problem still exists, continue on.

    Disable automatic login
    While in safe mode, disable automatic login.

    1. Open System Preferences
    2. Click on "Accounts"
    3. Click "Login Options" on the bottom of the left pane
    4. You will probably have to authenticate, so click the lock in the bottom right corner and enter your password
    5. At the top, change "Automatic login" to "Off"
    6. Reboot

    Allow the Mac to boot normally

    Safe Login
    1. If you get to the login window successfully, we have ruled out a number of potential problems (Launch Daemons, StartupItems (outdated launch daemons), fonts, 3rd party kexts, etc.)
    2. Click your name (or type your username, depending on your login window settings)
    3. Enter your password but do not hit enter/return
    4. Hold down the shift key
    5. While holding shift, click the "Login" button

    If it logs in properly then, as I suspected, the problem would be Local and User LaunchAgents.

    These are located in ~/Library/LaunchAgents and /Library/LaunchAgents. (* NOTE, older versions of OS X utilize the LoginItems folder *)

    Few LaunchAgents
    It is likely that you have very few LaunchAgents in either Library, or maybe just one. In that case, moving the that item to your Desktop is an easy way to determine if that is the cause.

    To do this:

    1. Navigate to the LaunchAgent folders listed above
    2. Move the plist(s) to your Desktop (if you have plists in both, you may want to create folders called Local and User to separate them if you wish to put them back)
    3. Now, reboot (or logout) and try to login normally, if it works one of those items is the problem

    Many LaunchAgents: Narrowing it down
    Everyone has a different setup with various 3rd party software. So I can't tell you what exactly is causing it, but you can solve it with some detective work. If you have a lot of LaunchAgents, thinking about your system and what may be causing it will help you narrow it down.

    1. Think about what 3rd party software you have and specifically what loads at startup. Based on what is happening, it may be something that adds to or modifies the GUI in some way.

    2. Looking at the logs during a failed login attempt may illuminate you as to the point of failure.

    To do this, open up Console (/Applications/Utilities/Console) and navigate to a time when a login failure occurred. If the above guidance led you to Launch Agents, then you will be looking for lines that have a Sender[PID] of com.apple.launchd.peruser.UID, where UID is your user ID (the first account on a Mac has a UID of 501).

    3. If you have an idea of what it may be, simply navigate to one of the LaunchAgent folders listed above and move the plist from the folder.

    The name *should* relate to the developer that created it and it will be in reverse domain format, for example: com.adobe.XXX or com.google.XXX

    Update your software

    If you have determined what the problem is, check for an update for that software. As the developer may have fixed whatever incompatibility arose.

    If there is no update, alert the developer and work with them to solve the problem. And for now, remove the LaunchAgent until the problem is fixed.


    I know this is a lot of info, but being in tune with your system helps make troubleshooting much easier. You may already have an idea of what may be causing, or can easily narrow it down. Feel free to report back with new information and I can walk you through solving the problem.

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