3 Replies Latest reply: Aug 25, 2013 6:52 AM by Linc Davis
duanrab Level 1 Level 1 (0 points)



I have a Macbook pro medio 2012. Everything works fine except the WIFI. I'm running on OS X Mountain Lion 10.8.4 now.


When I open my macbook pro (after sleep mode) to go on the internet/ whatever I have sometimes (1 time on 3) a problem that the my macbook pro can't connect to the internet. In the status bar on the top of the screen there is an exclamation mark instead of the WIFI strength.  The  problem is: self-assigned IP address of X and will not be able to connect to the internet.

If I open network preferences and shut the wifi off and on it is fixed. Or when I click in the network preferences on 'assistance' and then diagnostic info and follow the steps. After I folow these steps my wifi is 'repaired' and I am able to connect to the internet.


At home we have different mac's and another macbook pro which never have this problem. It only happens with my macbook pro.

The same problems occurs when I try to connect on another wifi netword at a friend's place or at my university.



Do you think this problem is a hardware problem? (if Yes, I have only 2 months of warranty left from Apple).

Or do you now how I can fix this?



Thank you in advance!

Have a great evening.

MacBook Pro, OS X Mountain Lion (10.8.4)
  • Linc Davis Level 10 Level 10 (169,525 points)

    Click the lock icon in the lower left corner of the Network preference pane and authenticate, if necessary. From the Location menu at the top of the window, select Edit Locations. A sheet will drop down. Click the plus-sign button to create a new location. Give it any name you want. In the new location, set up the Wi-Fi service with the same settings you used before. Click Apply and test.

  • duanrab Level 1 Level 1 (0 points)

    Thank you for your response Linc Davis. But unfortunately this didn't solve my problem. It still occurs that my macbook pro shows the exclamation mark in my status bar after waking him up after sleep mode. Do you have any other advice for solving this?

    Thank you!

  • Linc Davis Level 10 Level 10 (169,525 points)

    Back up all data before making any changes.
    Step 1
    Take all the applicable steps in this support article.
    Step 2
    If you're running OS X 10.8.4 or later, run Wireless Diagnostics and take the remedial steps suggested in the summary that appears, if any. The program also generates a large file of information about your system, which would be used by Apple Engineering in case of a support incident. Don't post the contents here.

    Step 3

    If you're not using a wireless keyboard or trackpad, disable Bluetooth by selecting Turn Bluetooth Off from the menu with the Bluetooth icon. If you don't have that menu, open the Bluetooth preference pane in System Preferences and check the box marked Show Bluetooth in menu bar. Test. Continue if you find that Wi-Fi is faster with Bluetooth disabled.

    From that same menu, select Open Bluetooth Preferences. If the box labeled Discoverable is checked, uncheck it. Click the Advanced button, and in the sheet that opens, uncheck the top three boxes, if any are checked. Click OK. Enable Bluetooth and test again.

    If the application called "Bluetooth Setup Assistant" is running, quit it.

    Step 4

    This step will erase all your settings in the Network preference pane. Make a note of them before you begin, and recreate them afterwards. It may be helpful to take screenshots of the preference pane.

    Triple-click the line below on this page to select it:


    Right-click or control-click the highlighted line and select

    Services Reveal

    from the contextual menu.* A folder should open with an item named "SystemConfiguration" selected. Move the selected item to the Trash. You may be prompted for your administrator password.

    *If you don't see the contextual menu item, copy the selected text to the Clipboard (command-C). In the Finder, select

    Go Go to Folder...

    from the menu bar, paste into the box that opens (command-V). You won't see what you pasted because a line break is included. Press return.

    Reset the System Management Controller.

    Step 5


    Make a "Genius" appointment at an Apple Store, or go to another authorized service center.

    Back up all data on the internal drive(s) before you hand over your computer to anyone. There are ways to back up a computer that isn't fully functional — ask if you need guidance.

    If privacy is a concern, erase the data partition(s) with the option to write zeros* (do this only if you have at least two complete, independent backups, and you know how to restore to an empty drive from any of them.) Don’t erase the recovery partition, if present.


    Keeping your confidential data secure during hardware repair

    *An SSD doesn't need to be zeroed.