can't connect to internet, always get (169.254) ip address

Question

P D Author

Level 1

8 points

can't connect to internet, always get (169.254) ip address

Mac Mini with OS X 10.5.8

Internet connection worked for years up til now.

I know the Comcast modem is working because my other computer accesses service fine.

I only connect directly from the Comcast modem to a single computer at any one time (to prevent conflicts).

I have disconnected the battery from the Comcast modem and rebooted the modem and my computer.

I have called Comcast and had them troubleshoot the line and reset the modem. All looks fine from their end.

I have trashed all plist files that have to do with the network (and let the computer regenerate new ones). I then reconfigured the network and the settings in Network seem exactly the same.

Any ideas? Could a bad internal battery be enough to cause this? Should I zap PRAM? Any suggestions will be entertained. Thanks, Peter

(Also, in Proxies dialog, I tried removing the info (*,local, 169.254/16) in the "Bypass Proxy Settings for These Hosts and Domains" and it would cause the "Configure Proxies" selection to default to "Always Use PAC File". Had to go back and retrash all the plist files to have Proxies go back to "Configure Proxies-Manually".

Here are my settings:

Mac mini, Mac OS X (10.5.8)

Posted on Jun 4, 2011 10:21 AM

Reply

Answer 1

BDAqua

Level 10

245,645 points

Jun 4, 2011 10:52 AM in response to P D

Hi, the pics can't be viewed here for some reason.

Has this Mac needed Proxies at all before???

Any 169.254.x.x IP is called a Self assigned IP, meaning the Modem or Router isn't handing out one.

How does it connect, Ethernet, Airport, otther?

Reply

Answer 2

P D Author

Level 1

8 points

Jun 4, 2011 11:02 AM in response to BDAqua

Strange. The pictures show up for me.

Ethernet.

Don't know about Proxies. I originally set up the network connection years ago.

This Mac Mini network is set up identically to my G5 network and the G5 works.

Reply

Answer 3

BDAqua

Level 10

245,645 points

Jun 4, 2011 11:15 AM in response to P D

The pics must be on your Mac then I think, did you use the Insert Images "From your computer" button?

Does the G5 use Proxies?

It seems that you're aware if this aleady from what you've done, butjust so we don't miss something, a Modem must be powered down for say 5 minutes before it'll recognize a new device, otherwise it'll only talk to the last device connected.

Reply

Answer 4

BDAqua

Level 10

245,645 points

Jun 4, 2011 1:27 PM in response to P D

This what I get for every pic...

Reply

Answer 5

P D Author

Level 1

8 points

Jun 4, 2011 2:54 PM in response to BDAqua

In my G5 (OS X 4.11) the Network area for Proxies has "Configure Proxies" set to "Manually", same as Mac Mini (OS X 5.8); that's why I can't understand the ability of one to work and not the other. (I'm fairly clueless about all the jargon in the Network configuring process, so asking me about proxies, etc will garner few informed response.)

Yes, I did use the "Insert Image" command. Don't know why it would be messed up. I will try again here.

And I'll try powering down the Modem for a longer period. Thanks.

Reply

Answer 6

BDAqua

Level 10

245,645 points

Jun 4, 2011 3:10 PM in response to P D

OK, they show now for some reason.

On the 3rd pic, highlight Web Proxy & Secure Web Proxy, see what thay say.

On the G5 works, what are the 1st two IP numbers?

Reply

Answer 7

P D Author

Level 1

8 points

Jun 4, 2011 3:40 PM in response to BDAqua

No success on the longer modem power down and power up.

Tried highlighting Web Proxy & Secure Web Proxy on Mac Mini. No additional info or information. (See pict 1 below).

Also, you can see the IP numbers for the G5 (see pict 2 below).

Reply

Answer 8

BDAqua

Level 10

245,645 points

Jun 4, 2011 4:14 PM in response to P D

Well, without the G5 connected you might try Manually for Configure IPv4 with those numbers for a test.

Do you remember the .plists you trashed?

Might also Turn OFF IPv6 & reboot.

Reply

Answer 9

P D Author

Level 1

8 points

Jun 4, 2011 7:14 PM in response to BDAqua

I'll try those.

Plists trashed from library/preferences/systemconfiguration:

com.apple.network.identification.plist

networkinterfaces.plist

preferences.plist

Reply

Answer 10

P D Author

Level 1

8 points

Jun 4, 2011 7:33 PM in response to P D

No luck on last suggestions.

As I said in my first post entry, in Proxies dialog, there is this info (*,local, 169.254/16) in the "Bypass Proxy Settings for These Hosts and Domains". This info does NOT appear in the network settings of my G5. It does seem suspect because it has the first six numbers (169.254) of the IP address that keeps appearing in my Mac Mini network settings (and that is a self-assigned IP address which seems to be the problem).

And as I stated earlier, deleting the info (*,local, 169.254/16) in the "Bypass Proxy Settings for These Hosts and Domains" would cause the "Configure Proxies" selection to default to "Always Use PAC File". This didn't solve the problem, so I returned the info back to the "Bypass Proxy Settings for These Hosts and Domains" area.

Do you think this info (*,local, 169.254/16) is part of the problem?

I'm at the end of solutions. Can't think of anything else to do. I'm open to drastic or far-fetched ideas.

Thanks for all your time and attention.

Reply

Answer 11

BDAqua

Level 10

245,645 points

Jun 5, 2011 10:23 AM in response to P D

>Do you think this info (*,local, 169.254/16) is part of the problem?

Off hand I don't think so at all, but seems at one time this settup used a Proxy Server, but should only have any effect if there was a Proxy Server entered!?

http://support.apple.com/kb/TA23188?viewlocale=en_US

http://docs.info.apple.com/article.html?path=Mac/10.5/en/8760.html

It seems the problem is either the Mac not talking to the Modem, or the Modem not talking to the Mac, a cheap Router might solve this problem... the Modem talks to the Router, the Router hands out IPs to several computers at once, no need to switch connections.

Does this same Ethernet cable work on the G5 on the same Modem port?

If your G5 has Airport also, we could try Internet Sharing on the G5... In the G5's Sharing Pref Pane, enable Web Sharing & Internet Sharing, on this last choose "Share your connection from:" Ethernet, to Computers Using Airport just before enabling it, then under the Airport Icon choose Create Network... wait a bit &see if the Laptop can join that network & get Internet.

Reply

Answer 12

P D Author

Level 1

8 points

Jun 5, 2011 12:02 PM in response to BDAqua

I read both links. No luck.

G5 and Mac Mini both get hooked up identically; I just switch the same Ethernet cable between them. The modem must be communicating, I assume, since the G5 hooks up to the Internet.

Also, no Airport on the G5, so that suggestion won't work.

Is there a way to completely trash all network settings and just start over? I assumed I did that when I deleted the files from library/preferences/systemconfiguration, but maybe there are other files that effect the network? One website suggested trashing the whole library/preferences folder (non-user); that seemed a bit scary, so I didn't do it, but what do you think? Will all the plist files in the library/preferences folder (non-user) get regenerated?

Your efforts are Herculean and I appreciate every nanosecond of your time.

Bizarre that this is so hard to solve; I imagined it would be easy.

Is there a way to completely reinstall an new copy of the network software or something like that? Perhaps it's corrupted? (No way to Software Update directly, though, since no Internet connection).

I'll take one more round of suggestions (if you have them), then I'll try other avenues. May need an in-house pro or something.

Thanks again. Peter

Reply

Answer 13

BDAqua

Level 10

245,645 points

Jun 5, 2011 1:32 PM in response to P D

Well, some other plists that may affect it are...

Best done with, Safe Boot , (holding Shift key down at bootup), use Disk Utility from there to Repair Permissions.

Users/YourUserName/Library/Preferences/ByHost/com.apple.networkConnect.<12 digit number>.plist

/Users/YourUserName/Library/Preferences/com.apple.internetconnect.plist

/Library/Preferences/SystemConfiguration/preferences.plist

/Users/YourUserName/Library/Preferences/com.apple.systempreferences.plist

/Library/Preferences/SystemConfiguration/com.apple.airport.preferences.plist

/Library/Preferences/com.apple.sharing.firewall.plist

/Library/Preferences/SystemConfiguration/NetworkInterfaces.plist

/Library/Preferences/com.apple.networkConfig.plist

/Library/Preferences/SystemConfiguration/com.apple.nat.plist

Reboot.

Does the G5 have one or two Ethernet ports?

Another test would be to try a New Admin User in Accounts Pref Pane, log out of this account & into the new one, see if it work in a new account after a complete 5 minute power down of the Modem. Did you say it has a Battery in it?

Reply