SELF-ASSIGNED IP??? (ethernet)

[pertusis1]

A new idea

Hello. I recently changed routers to a Bandluxe R305 when we moved into our new home. My iMac running a 2.4 GHz Intel Core 2 Duo seemed to be working OK until I randomly ran into the problem with the 'self-assigned IP' problem. It rendered me completely unable to connect to the internet. Having gone through this entire forum and having tried a bunch of stuff, nothing worked...

Until I realized that the only thing that had changed was that I turned on an old Macbook laptop as well as an old Powermac dual G4 867 (yes, it still runs dual systems with OS9 and OSX At that point, I was attempting to attach 4 devices to my wifi (iMac, MacBook, Powermac, iPhone 3GS).

I turned off my G4 and disconnected my iPhone from the wifi network, and BINGO! My iMac connected without any trouble. No guarantees on any of this, but I suspect my wifi router can only maintain a certain number of simultaneous connections (2 or 3). For those of you dealing with this very frustrating problem, you might consider unplugging all of your devices from wifi and see if your computer then works.

God bless you all. The macrumors community has been very helpful to me over the last few years.

 

[drdos]

Hey guys,

I was having the same issue you guys were having, and have tried everything. but I finally figured out the issue thanks to you guys.

the damn ipfw!

I even checked to see if it was running the process library

ps ax | grep ipfw

not found.

So I figured what the hell why not try this..

Open up the terminal and sudo into root.
then i typed in - ipfw flush
then it will ask you are you sure? hit Y then Bam no more self assigned IP address.

I found this thread via google and thought I would add my 2 cents to it to help others having the same issue.

 

[Superman07]

Hey guys,

I was having the same issue you guys were having, and have tried everything. but I finally figured out the issue thanks to you guys.

the damn ipfw!

I even checked to see if it was running the process library

ps ax | grep ipfw

not found.

So I figured what the hell why not try this..

Open up the terminal and sudo into root.
then i typed in - ipfw flush
then it will ask you are you sure? hit Y then Bam no more self assigned IP address.

I found this thread via google and thought I would add my 2 cents to it to help others having the same issue.

Interesting. Do you have step by step direction for somebody less familiar with terminal? Did you need to check for your ipfw outside of terminal?

 

[drdos]

Interesting. Do you have step by step direction for somebody less familiar with terminal? Did you need to check for your ipfw outside of terminal?

sure do the following

Goto Applications
open up Utilities folder
In there look for an Application that is called Terminal
You should see a window open up that is black or white depending on your settings
There you can type stuff for commands you need to execute.

Type the follow command first to access root control:

sudo su

then hit the return key

It will then prompt you for your password. Enter your password and hit enter.

then it should say something like "sh-3.2#" now type the following command

ipfw flush

then hit the return key - it will then ask you 'Are you sure' or something like that. simply hit the Y key. Thats it!

Once you have done that, type in exit then hit the return key to exit out of root.

then close out the terminal program.

 

[Superman07]

sure do the following

Goto Applications
open up Utilities folder
In there look for an Application that is called Terminal
You should see a window open up that is black or white depending on your settings
There you can type stuff for commands you need to execute.

Type the follow command first to access root control:

sudo su

then hit the return key

It will then prompt you for your password. Enter your password and hit enter.

then it should say something like "sh-3.2#" now type the following command

ipfw flush

then hit the return key - it will then ask you 'Are you sure' or something like that. simply hit the Y key. Thats it!

Once you have done that, type in exit then hit the return key to exit out of root.

then close out the terminal program.

Thanks for the tip, but it didn't seem to solve the problem.

 

[ajs14221]

Finally working!

Hardware:
Macbook Pro 15" originally installed with Snow Leopard
Actiontec MI424WR router

The gory details:
Wanted to erase and reinstall hard drive as Macbook was passing from husband to son. (I also have a Macbook Pro thank goodness - don't know what I would have done without another working machine). Well, Lion is available at the Apple Store now but it wasn't when I started.
Used disk utility to erase and reformat the drive.
Used the original install disk that came with my Macbook to reinstall Leopard but it crapped out - 3 times.
What to do now? I'd already downloaded and installed Lion on my and my husband's new Macbook Air without creating a boot disk. Thanks to an article by HighTechDad I was able to re-download the Lion package and create a boot disc on my machine.
3 goes later and my clean Macbook Pro has Lion installed. I used an ethernet cable from it to the hub to access the internet for any stuff that needed downloading during the install. OK, so we're sweet, I want to move it off the ethernet and connect using wifi.

self-assigned ip was what met me.

So, I end up at at a number of different forums when I go searching for a solution. After many frustrating hours over a period of days I am up and running again thanks to this thread on MacRumors (which unfortunately wasn't the first one I visited). Thank you, thank you, thank you, to everyone who contributed but particularly to ted400. KEYCHAIN, KEYCHAIN, KEYCHAIN!!!

I tried everything I found (many times) in various forums in roughly this order:
* Shutdown, unplugged and rebooted everything - no joy.
* reset wireless router to factory settings - no joy.
* took the Macbook to a local Starbucks with free wireless access - no problem connecting whatsoever!!!
* Made a number of new locations each with different dhcp (manual, automatic, etc. etc.) settings - no joy.
* renewed the lease more times than I care to mention - no joy.
* removed (actually renamed as I don't like removing files in system directories) the 3 files mentioned in /Library/Preferences/SystemConfiguration - no joy.
* allowed all incoming connections in System Preferences -> Security -> Firewall
* flushed the ipfw cache
* checked the keychain permissions for the network login and device - allowed all applications to access this device - still no joy

So now I'm pretty much concluding that nothing is going to work for me and I may as well try anything because I'm probably going to have to reinstall again. Thus I remove anything in the keychain related to the wireless device (in both the login and system areas) and BINGO! I reboot and am asked for the WEP password and I'm in!!! I had to pull up a number of web pages I knew I hadn't visited and therefore weren't in my cache before I actually believed it.

It seems to me that if I'd just done this first everything would have been fine - I don't think any of the other things I did were actually necessary.

 

[stroked]

sure do the following

Goto Applications
open up Utilities folder
In there look for an Application that is called Terminal
You should see a window open up that is black or white depending on your settings
There you can type stuff for commands you need to execute.

Type the follow command first to access root control:

sudo su

then hit the return key

It will then prompt you for your password. Enter your password and hit enter.

then it should say something like "sh-3.2#" now type the following command

ipfw flush

then hit the return key - it will then ask you 'Are you sure' or something like that. simply hit the Y key. Thats it!

Once you have done that, type in exit then hit the return key to exit out of root.

then close out the terminal program.

I did this to both of my G4 laptops (Leopard) after seeing this post, and I haven't had the self assigned IP since. THANKS

 

[idnotso]

My solution

I have a 2009 iMac that suddenly started getting the self-assigned IP (169) and could not connect to the internet via ethernet cable modem. However, I could connect and get a correct IP when I turned my computer off and started it in safe mode, so I knew there was nothing wrong with my ethernet cable or modem. Safe mode disables sound and other processes that would normally load on start up. Safe mode is achieved by holding down the shift key while powering up your computer.

I still wanted my computer to work normally, and even after searching many hours and trying many different suggestions, all that did not work for me, I finally called Apple Care and got a solution. If you find that you can connect in safe mode, but not in regular mode, try the following:

Shut down

Restart, then hold down shift button when blue screen appears (if you do this on the first gray screen, you are entering safe mode) This brings you to your log in screen

Enter (your) password, hold down the shift key, then press return. This disables all start up items. In fact, safe mode disables all start up items, but your system is only half there. This method disables them, and you have full functionality, minus the start up items.

Try your internet connection again, if it works then something in start up is causing the problem. Mine worked, so I needed to look at my start up items. I went to System Preferences, System, Accounts, (my) Admin.

There are two buttons up top, Password and Login Items. Choose Login Items and see what is there. In my case, I had iTunesHelper, that was checked, and SophosUIServer that was unchecked. Sophos is an antivirus program for Macs.

Even though Sophos was unchecked, I needed to remove it from the window. At the bottom of the window is a + and - sign. Click on the item or items you want removed (in my case, Sophos) and then click on the - button. If the - button is grayed out, you may have to click on the lock in the lower left corner and enter your admin password to make changes.

I shut down and then restarted. I was able to immediately connect to the internet through my ethernet cable. Happy Day! As a test, I put my computer to sleep and then woke it by moving my mouse. the same problem happened again-no connection! But wait! Within about 5 or 6 seconds, my computer connected itself again.

To fix this, go to System Preferences, Hardware/ Energy Saver, and make sure the box is checked for "Wake for network access."

Gosh, I was having the worst thoughts about "Corporate" Apple forgetting about the little guy (me), but their Apple Care line actually helped me this time. I hope this information helps others with this issue. In my case, it was my Sophos Antivirus that was interfering with my internet connection. I guess you could say that Sophos is 100% effective at stopping viral infections!

 

[Mal]

In my case, it was my Sophos Antivirus that was interfering with my internet connection. I guess you could say that Sophos is 100% effective at stopping viral infections!

Heh. Unfortunately, it's better at causing other problems than it is at catching malware. If you haven't already, I'd definitely recommend uninstalling it. If you need a good free anti-virus, try ClamXav.

jW

 

[GGJstudios]

In my case, it was my Sophos Antivirus that was interfering with my internet connection.

I agree with Mal. I recommend that you avoid using Sophos, as it could actually increase your Mac's vulnerability, as described here and here.

 

[presseddesigns]

Hi

I'm a complete noob. Just bought my first Mac a few weeks ago. Although I have worked on them in offices for a few years, setting them up and troubleshooting them is not something I am a pro at....yet.

I have read *most* of this very long thread, as I too am having the same issue. I am only getting the issue if the computer has been connected to the network for an extended period of time.

I just went to my router page ans assigned myself a static IP via my MAC address. It seems to be sticking. Can anyone tell me if this is a good idea or not? I'd like to suggest it as a way to solve the issue, but just wondering if there are any repercussions.

I'm on a Mac Pro running Lion

 

[andytwelveten]

Conflicting IP Address - I don't understand

Hi, can someone tell me how to create a new post please? (having a blond moment)

I have just moved house, I use a Mac Pro (10.7.4) and a Mac Book Pro (10.7.4)
On the desktop I use a wireless dongle to connect to BT Broadband Router,
The laptop uses its own wireless to connect to the router.
We also have 2 other PC Laptops that connect wirelessly to the router.

The internet is very temperamental, keeps dropping off and I have to restart the router.

I keep getting a message on my desktop saying -

"Another device on the network is using your computers IP Address.
If you continue to have problems, change the IP Address of this computer or the IP address of the other device"

Is this something that could be causing problems for the router?

ANd how do I go about fixing the issues as I am totally useless once the word network is used!!

Apologies for posting in the wrong place, and any help will be really appreciated!!

Many thanks
Andy