MacBook Pro not getting IP address via DHCP

[kenchie]

I have an early 2008 MBP running Lion 10.7.5. on a corporate LAN. Recently it has refused to pick up IP addresses via DHCP on both the ethernet and wifi interfaces. I have tried the following without success;

1. New network location
2. Different ethernet connection via USB adaptor
3. Trashing keychain entries for corporate network
4. Trashing network prefs plist files
5. Reset PRAM
6. New user account

None of the above made any difference, it just defaults to a 169.254 IP address and not the 10.128 range that the network requires.

If I enter recovery mode, the ethernet works fine and can access the internet.

Any ideas please?

Thanks.

 

[Bruno09]

Hi,

Some ideas :

1. repair the permissions using Disk Utility, then test the connexion

2. boot in safe mode (Shift key), test the connexion

3. trash the whole Macintosh HD/Library/Preferences/SystemConfiguration folder, then reboot.

 

[kenchie]

Hi,
3. trash the whole Macintosh HD/Library/Preferences/SystemConfiguration folder, then reboot.

Thanks very much, this worked!

 

[gdt95]

#3 worked for me too. OS X Yosemite.