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

[samat2001]

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?

 

[MisterMe]

• 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.

 

[samat2001]

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...

 

[Cerebrus' Maw]

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...

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=

 

[samat2001]

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=

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...

 

[lostngone]

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...

Did you check to see if any firmware upgrades are available for your current router?

 

[samat2001]

Did you check to see if any firmware upgrades are available for your current router?

I did...there haven't been any since 2006 lol

 

[Cerebrus' Maw]

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...

As above, check for Firmware Updates. In the TCP/IP settings, is the IPv4 set to DHCP?

 

[lostngone]

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?

 

[Cerebrus' Maw]

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?

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

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.

 

[samat2001]

As above, check for Firmware Updates. In the TCP/IP settings, is the IPv4 set to DHCP?

Thanks for your response. IPv4 is set to DHCP and there are no firmware updates available.

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?

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...

 

[trainguy77]

What type of router is it?

 

[samat2001]

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

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.

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.

 

[samat2001]

What type of router is it?

It is a Linksys WRT54GS

 

[Cerebrus' Maw]

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...

Unsecured networks FTW!

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*

 

[lostngone]

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

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.

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

 

[Cerebrus' Maw]

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 is setup correctly and the client is firewalled the DHCP server will even deal this because because it arp and ping before it tries to assign an address.

I'll give it a go tonight. I'm fairly sure the router wont give it, but I could be wrong...

 

[trainguy77]

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*

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.

 

[Cerebrus' Maw]

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.

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....)

 

[trainguy77]

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....)

Yes thats true it can be changed. And the default is different depending on the DHCP service.

 

[lostngone]

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.

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.

 

[trainguy77]

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.

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.

 

[samat2001]

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.

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.

 

[Cerebrus' Maw]

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.

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...

 

[trainguy77]

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.

So the subnet and router are correct? if so go into network utility and attempt to ping the router address.