Can't connect to the internet no matter what I do...

Discussion in 'macOS' started by samat2001, Jan 7, 2009.

  1. samat2001 macrumors newbie

    Joined:
    Jan 7, 2009
    #1
    Hi guys

    I'm having a real headache trying to get online with my brand spanking new Macbook Pro. I've tried to connect in two ways - firstly through ethernet cable straight into my modem. It says I have a 'self-assigned IP Address' and it won't connect. I try connecting the modem to a wireless router, and try connecting to the wireless router using the wifi on the macbook pro, but it says I can't find an IP address. I have been on the phone to the Apple tech guys for almost an hour, and we tried various things from resetting the modem, router, reinstall OSX etc, but it didn't work. I'm thinking it may be down to my Internet Service provider (I'm with Virgin Media in the UK), but I have two other laptops (Windows based) which don't cause me any problems.

    Has anyone come across anything like this before?
     
  2. MisterMe macrumors G4

    MisterMe

    Joined:
    Jul 17, 2002
    Location:
    USA
    #2
    • Remove the power from your modem for 30 seconds.
    • Plug your MacBook Pro into a LAN port of your router.
    • Run Ethernet from the WAN port of your router to the Ethernet port of your modem.
    • Repower the modem.
     
  3. samat2001 thread starter macrumors newbie

    Joined:
    Jan 7, 2009
    #3
    Thanks for the advice. I tried this but unfortunately it did not work. I have managed to connect to the internet by plugging straight from the Modem to the macbook (bypassing the router) - I tried this last night and it didn't work but I have just tried it and it works. Over wifi, I still get the 'No IP address' problem though...
     
  4. Cerebrus' Maw macrumors 6502

    Joined:
    Mar 9, 2008
    Location:
    Brisbane, Australia
    #4
    When you try to connect to you router via Wireless, does your Airport icon on the top right go black?
    Any security? Maybe your wireless only hands out specific IP address? Is it set to Distribute IP address Dynamically?
    Also, goto your network settings, and select Advanced on Airport. Under TCP/IP, what are the settings?

    Sorry for all the questions, but wireless problems could be a phlotora of possible problems.... D=
     
  5. samat2001 thread starter macrumors newbie

    Joined:
    Jan 7, 2009
    #5
    Not at all - thanks for taking the time to help.

    It does go black yeah - it is definately connecting to the router, but I think it is probably something to do with the router, because it is not giving the macbook an IP address to use (though funnily enough there are no problems when using our other two laptops, though they are windows based). There is WPA security, and we have tried disabling the security to see if that works but it didn't work. The router is set up to distribute and manage the IP addresses. When I look under the TCP/IP settings in airport, it doesn't give any details. I have tried manually typing in the IP address, but I then get the 'Self-assigned IP Address' error message, and it still doesn't work.

    I can get online when I plug the modem straight into the macbook pro, it's just when it's going through the router that it doesn't seem to work. (And it doesn't work if you take a cable from the router into the macbook). I'm wondering whether I should just try buying a new router...
     
  6. lostngone macrumors 65816

    lostngone

    Joined:
    Aug 11, 2003
    Location:
    Anchorage
    #6
    Did you check to see if any firmware upgrades are available for your current router?
     
  7. samat2001 thread starter macrumors newbie

    Joined:
    Jan 7, 2009
    #7
    I did...there haven't been any since 2006 lol
     
  8. Cerebrus' Maw macrumors 6502

    Joined:
    Mar 9, 2008
    Location:
    Brisbane, Australia
    #8
    As above, check for Firmware Updates. In the TCP/IP settings, is the IPv4 set to DHCP?
     
  9. lostngone macrumors 65816

    lostngone

    Joined:
    Aug 11, 2003
    Location:
    Anchorage
    #9
    I do not understand the 'Self-assigned IP Address' error you are seeing if you set it to manual and give it another address in same subnet address range that the other systems that are working I don't know why you would be seeing that error?

    Also you don't have any MAC address filtering setup on that router do you?
     
  10. Cerebrus' Maw macrumors 6502

    Joined:
    Mar 9, 2008
    Location:
    Brisbane, Australia
    #10
    I believe, if you set a router to Dynamically give IP address, and then use a client to manually get an IP address, the router wont distribute it, since it may be in use already. Also, it would kind of defeat the purpose if you could type in any range between 192.168.0.1 - 192.168.0.255 :p

    Edit: Just as a test, if your mac is set to DHCP, change it to manual with DHCP, click ok/apply, then go back and put it to DHCP and apply again.
     
  11. samat2001 thread starter macrumors newbie

    Joined:
    Jan 7, 2009
    #11
    Thanks for your response. IPv4 is set to DHCP and there are no firmware updates available.



    No mac address filtering...and yeah it's weird that I get the 'self-assigned' error message why trying to configure it myself. It's a complete mystery.

    I should also say that I managed to get onto my neighbours network without a problem so hopefully that means it's not a fault with the mac itself, and probably a fault either with my ISP or the router...
     
  12. trainguy77 macrumors 68040

    Joined:
    Nov 13, 2003
  13. samat2001 thread starter macrumors newbie

    Joined:
    Jan 7, 2009
    #13
    Thanks for the suggestion. I tried this, and when I had the DHCP manual, it changed to 'Self-Assigned...'. When I switched back to DHCP, it said no IP address again. How totally weird. I have the router settings open now and i'm frantically looking through it to see if there is anything that is turned on/off that shouldn't be.
     
  14. samat2001 thread starter macrumors newbie

    Joined:
    Jan 7, 2009
    #14
    It is a Linksys WRT54GS
     
  15. Cerebrus' Maw macrumors 6502

    Joined:
    Mar 9, 2008
    Location:
    Brisbane, Australia
    #15
    Unsecured networks FTW! :p

    Ok, thats good news. Then it must be something obscure with the router. Just to make sure it is distributing DHCP, turn off one of the windows boxes totally, so its not connected to your network. This should free up "one" IP address, and see if it works.

    We'll get it in the end!!! *shakes fist at sky*
     
  16. lostngone macrumors 65816

    lostngone

    Joined:
    Aug 11, 2003
    Location:
    Anchorage
    #16
    I will admit I have not tried this on a Mac, but you should be able to just force an address as a test.

    Just set it to manual and pick a address that is not already in use that is within the same subnet and you will need to set the mask, default gateway and DNS as well but it should work. If the DHCP server is setup correctly and the client ISN'T firewalled the DHCP server will even deal with this because it arp's and pings before it tries to assign an address.

    Edit: ISN'T
     
  17. Cerebrus' Maw macrumors 6502

    Joined:
    Mar 9, 2008
    Location:
    Brisbane, Australia
    #17
    I'll give it a go tonight. I'm fairly sure the router wont give it, but I could be wrong...
     
  18. trainguy77 macrumors 68040

    Joined:
    Nov 13, 2003
    #18
    It won't free up the IP. DHCP is set up on a lease basis. So even if the system is off the IP is reserved for a certain amount of time. Normally a couple of days.
     
  19. Cerebrus' Maw macrumors 6502

    Joined:
    Mar 9, 2008
    Location:
    Brisbane, Australia
    #19
    Gah, sorry, I ment to add "and refresh the router".
    I also think it varies from router to router. On the Netgear I use at home, by default, it's just set to 4 hours, so when i come back with my ipod touch, and depending on my PS3/macbook/roomates, i get different IP's.

    (I've got to stop refreshing this forum....)
     
  20. trainguy77 macrumors 68040

    Joined:
    Nov 13, 2003
    #20
    Yes thats true it can be changed. And the default is different depending on the DHCP service.
     
  21. lostngone macrumors 65816

    lostngone

    Joined:
    Aug 11, 2003
    Location:
    Anchorage
    #21
    If you take an ip address(manual assign) of a machine that is off, but is already in the DHCP servers lease table the DHCP server (should not) try to assign it again.

    The reason is that the DHCP server will first look at its arp table/database and see if someone is already using it, then it will try and ping that address and if it doesn't get a response it will then hand it out to a machine.

    One problem is with Firewalled systems that block things like ICMP because the DHCP doesn't know someone using that IP because it doesn't respond to the ICMP(ping) request.
     
  22. trainguy77 macrumors 68040

    Joined:
    Nov 13, 2003
    #22
    Yeah i understand this. If when he assigns a IP manually (one not in use yet) it should function. As DHCP is taken out of the loop. If it still doesn't then its something else.
     
  23. samat2001 thread starter macrumors newbie

    Joined:
    Jan 7, 2009
    #23
    Thanks for all your replies. Unfortunately something still isn't quite right. I have tried assigning an IP address manually, and in the network settings it is showing as connected with the green light (as opposed to the orange or red light to indicate something is wrong), however it still won't access the internet. When I try and open Safari, it says it can't connect.
     
  24. Cerebrus' Maw macrumors 6502

    Joined:
    Mar 9, 2008
    Location:
    Brisbane, Australia
    #24
    Open finder, and goto the Mac Hard drive and i think goto

    Library/Preferences and at the bottom there should be a folder called System Configuration, with about 8-10 .plist files. (should be some along the lines of bluetooth, network settings, smb settings etc.) Pull this folder (Sys configuration) to the desktop, reboot, and try again...
     
  25. trainguy77 macrumors 68040

    Joined:
    Nov 13, 2003
    #25
    So the subnet and router are correct? if so go into network utility and attempt to ping the router address.
     

Share This Page