MacBook Pro won't connect to internet, previously used network

[Queen of Spades]

Tearing my hair out here, so if anyone has any suggestions, I'd appreciate it.

Details:
- 2011 13" MacBook Pro, running 10.7.4, fully updated
- regular WEP wireless network

This computer has connected to our wireless network just fine for the last 8 months. Out of the blue yesterday, it would connect to the network, but not the internet. Safari just hangs, itunes Store won't load, etc.

I've tried deleting and re-adding the network, emptying the cache, deleting and re-adding the wireless adapter, etc.

The weird thing is no matter how many times I delete the network, it always seems to remember the password. Is there some way I could completely obliterate all saved network settings? I thought deleting the networks from the list in System Preferences - Network would work, but alas it has not.

The computer connects fine to other networks, including an iPhone hotspot. Nothing has changed in the last couple of days. And creating a new user on the computer doesn't solve the problem.

Anyone have any ideas? I have a Genius Bar appointment for it (it's not my computer), but considering they will be trying to troubleshoot it out of range of the network that's giving the problems, I'm not all that confident anything is going to result.

Thanks in advance. And ugh.

 

[iLog.Genius]

Turn off AirPort/WiFi.

Finder > Macintosh HD > Library > Preferences > System Configuration:

move preferences.plist and com.apple.airport.preferences.plist to the trash and restart computer.

Try to connect/setup your wireless network again.

 

[Queen of Spades]

Turn off AirPort/WiFi.

Finder > Macintosh HD > Library > Preferences > System Configuration:

move preferences.plist and com.apple.airport.preferences.plist to the trash and restart computer.

Try to connect/setup your wireless network again.

Thank you for responding! Seriously.

It doesn't work, it just instantly re-creates the files, and still remembers the network password. I also tried deleting the whole folder at someone's suggestion, that didn't work either.

 

[iLog.Genius]

Thank you for responding! Seriously.

It doesn't work, it just instantly re-creates the files, and still remembers the network password. I also tried deleting the whole folder at someone's suggestion, that didn't work either.

It's suppose to recreate the file when you restart but it shouldn't remember all of your settings if you delete those files and/or folder...hmmm

Try creating a New Location in System Preferences > Network and connect, see what happens.

 

[Queen of Spades]

It's suppose to recreate the file when you restart but it shouldn't remember all of your settings if you delete those files and/or folder...hmmm

Try creating a New Location in System Preferences > Network and connect, see what happens.

Still nothing.

I checked one of our other macs' settings and inputted the DNS settings manually for our network, that also didn't work.

Genius Bar appointment yielded nothing, as I expected.

This is the most annoying/ridiculous problem I've come across - it connects to the network no problem, assigns an IP and everything, but nothing will load.

 

[iLog.Genius]

What happens if you try to connect to other wireless networks? That would help determine whether or not it's network related or something specific to your computer.

 

[doh123]

Your password is not saved as a preference, its in your keychain. You'll have to open up your Keychain Access.app (in Applications/Utilities) and find the entry for the network to remove the password.

 

[Queen of Spades]

What happens if you try to connect to other wireless networks? That would help determine whether or not it's network related or something specific to your computer.

Other wireless networks work just fine. It connected at the Apple store, at his house, and to my iPhone hotspot.

Every other computer in our office connects to the wireless network with no problem, except his.

 

[Mongus]

Are you able to reboot the wireless router? I have seen the same sort of behavior before and resetting the router often fixed it.

 

[Queen of Spades]

I did try that yesterday, but I may not have left it off long enough. He's gone for the day, so the nightmare will continue tomorrow.

Anyone that gives me the information that leads to this being fixed will get a little paypal or amazon donation.

I have thought about just reinstalling Lion and Time Machining his crap back in, but that'll take hours and it might just re-import whatever effed it up in the first place. Feel free to keep posting suggestions, I'll try them tomorrow and post back whichever one fixes it (if any).

Thanks again. Now I need a glass of wine.

 

[victorpienaar]

Security

I had this exact problem, what fixed it for me was a change of security mode on the router, had to change from WPA to WPA-PSK to WPA2-PSK, I aslo deleted the keychain entries and removed the Wireless Networks in Network settings, but I think the mode was the main issue.

 

[robertocitrix]

Going thru this problem HELP

Apple care could not figure it out today , I can connect anywhere but not at work. I erased the OS and installed a fresh mountain lion, everybody on my floor has a macbook pro every body can connect no problem, Nobody has a clue what could be, I can connect at home , Starbucks, university , hotspot anywhere. Late 2011 15' macbook pro mountain lion.

 

[MTLongson]

Similar Problem

I have a similar problem and I am fed up with tech support. I just bought my first Macbook Pro, and it will not connect to my home network with either a wireless connection or ethernet; however, it connects to my neighbor's fine. They keep insisting that it is the fault of my network, but my other devices, including my ipad and iphone work fine with it.

 

[Joshual200]

Hey everyone.

Looks like I'm next in line to have this issue. Computer died before I could plug it in yesterday. Reset time/date and I can't access my home wifi anymore. I have tried a lot of the suggestions that are on the forum (cleared keychain, repaired disk utility, etc.)

Has anybody been able to resolve this issue yet? Thanks a lot for the help.

 

[raptor402]

Have you considered a router issue? Does the router work with other devices?

I have a Linksys Wi-Fi Access Point set to bridge to my router. So, my router is the default gateway. However, sometimes, the access point giving its setup IP via DHCP to some devices on the internet. My solution was to simply set up static IPs for all devices. You could give that a shot.

Try resetting the access point and setting it up again. If you put in a different network name, it'll act as a completely new profile in the keychain.

Best of luck.

Regards
Raptor

EDIT:

Here are a few diagnostics:

1. Connect at least two devices on the network (including the device in question).
2. Check the IP addresses of each device.
3. Use the terminal to ping the other device from each device.

If that works, it's not an issue on the local network. Next step would be to check the router. If other devices on the network are able to connect to the internet, then it's not a router issue but an issue on the device itself. In that case, resetting the router and setting up a new network should do the trick.

You can also try connecting the MacBook to the same network via Ethernet to test the network.

 

[ToddJ]

Did anyone ever find a solution that worked? i am having the same problem.