How to fix Wi-fi Connection Timeout Error on iMac OS X Lion

I have been using iMac 21.5 and it was running on Snow Leopard but I have recently upgraded it to OS X Lion. Since then it is not able to connect to the network through wifi. I was not having any such issues with it previously and everything was working fine. I don’t know what has gone wrong with it after the update. When I am trying to connect to the network then it is giving me a "Connection Timeout Error". I don’t think that there is anything wrong with the network as other devices are able to connect to the same without any issues. I just wanted to know what might be the possible cause of this issue. What can I do to fix the same??

If you are getting "Connection Timeout Error" then you can try out the below trouble shooting tips and see if you are able to solve it out or not.

• You can try out Removing and re-adding network. For that go in to System Preferences > Network > Advanced > Wi-Fi tab and now just highlight the network with which you are having this issue and remove the same. Now re-add from the network dialog box or the menubar and click on the plus sign for expanding and selecting the preferred network.
• If that does not help then you can try out renewing the DHCP licence. For that go in to System Preferences > Network > Advanced > TCP/IP tab > "Renew DHCP Lease"
• If that does not help then you can try out changing the router settings. The router setting will vary from router to router but these are the common things that need to be changed.
• WiFi Channel Mode- set the WiFi Channel Mode to Auto Off and make use of single channel. If you want then you can make use of WiFi analyser for finding out the least congested channel.
• Password Encryption- you can try keeping it to Password Encryption rather than keeping it TKIP/AES. If you are getting the same error message with the dual mode then you can switch back to other single mode that might be available.
• Authentication Type- Try changing it to WPA-PSK or WPA2-PSK rather than WPA-PSK/WPA2-PSK. If you get the same error message when using WPA-PSK or WPA2-PSK then you can switch back to WPA-PSK/WPA2-PSK.
• Interface Type B/G- You can change it to B or G from 802.11b+g, if you are still getting the same error message after switching to B or G then you can switch back to 802.11b+g.

Just check out these things and you should be able to narrow down the cause of the issue and solve it out as well.

I have found that there are many people who are having such issue after upgrading to Mac OS X Lion. Many say that Mac OS X Lion is more sensitive as compared to Snow Leopard when wireless networking is concerned but I dint think its that. The cause of this issue is mostly wireless cards, wireless cards, routers or the combination of these two but you can try out the below workaround to find out the same.

1. You can start with Basic WiFi Troubleshooting like Turn wireless on & off, rebooting the Mac or Resetting the Router but if they are not making any difference in your case then you can proceed with the Advanced WiFi Troubleshooting methods.
2. The Advanced WiFi Troubleshooting includes setting up a manual IP address with DHCP, moving Wi-Fi to the top of the Service Order list, moving the router to the top of “Preferred Networks” list, deleting the existing WiFi connections and adding them again, adding an extra DNS entry, adding a New Network Location and so. You can go through the same in detail.
3. Setting up a manual IP address with DHCP- Go in to Network > Advanced > TCP/IP settings and use “DHCP with manual IP address”. Here you should Pick an IP which is in close range of the router.
4. Moving Wi-Fi to the top of the Service Order list- Here one has to prioritize WiFi as the primary method so that the system connects to the internet maintaining the connection.
5. Moving the router to the top of “Preferred Networks” list- You can access the “Preferred Networks” list by going in to “Advanced” menu in Network settings, you just have to Drag your primary router to the top.
6. Deleting the existing WiFi connections and adding them again- You have to click on the ‘minus’ icon for removing the existing WiFi connections and then click on the “+” for adding it back to the WI-Fi connection.
7. Adding an extra DNS entry- I am not sure about this but I have found a number of users mentioning that adding an extra DNS entry adding 8.8.8.8 which is Google’s public DNS to the list has helped them out.
8. Adding a New Network Location- Go in to the Network control pane and check out the ‘Location’ menu and move down to ‘Edit Locations’ and click on + sign for adding a new network Location, after renaming the same click on ok and select that “Network Name” and click on apply.

Hope that helps.

You can very well try out the troubleshooting tips that has been mentioned above but I just wanted to add that there are possibilities that the connection might be dropping because of the improper data transfer. If you want then you can try avoiding the same by pinging a random address, when you ping a random address some amount of data transfer occur because of the same which on the other hand helps to maintain your active network connection. For doing the same launch Terminal by going in to /Applications/Utilities/Terminal then “ping yahoo.com”. When you do same then you will get the below things in the command line.

Ping yahoo.com
64 bytes from 98.137.149.56: icmp_seq=91 ttl=52 time=27.806 ms
64 bytes from 98.137.149.56: icmp_seq=92 ttl=52 time=27.763 ms
64 bytes from 98.137.149.56: icmp_seq=91 ttl=52 time=27.806 ms
64 bytes from 98.137.149.56: icmp_seq=92 ttl=52 time=27.763 ms

Now just try connecting to the wifi in the background and see if it is making any difference in your case.

If you have updated to latest version of Mac OS X which is 10.6.3 and having issues in connecting to the Airport wireless connection then these are some more Wireless connection troubleshooting tips that you can try out.

• Change security protocol from WEP to WPA/WPA2
• Turn Airport on & off (via menu or Network preferences)
• Disable WPA/WEP protection
• Switch wireless channels – pick a channel no neighbor is using.
• Flush the DNS cache using the Terminal command: dscacheutil –flushcache
• Zap the PRAM on your Mac holding down Command+Option+P+R on restart
• Delete the com.apple.internetconfigpriv.plist and com.apple.internetconfig.plist files from ~/Library/Preferences
• Update your router firmware and Airport card firmware
• Trash your home directories SystemConfiguration folder and reboot- For doing this just delete all the files that are there in ~/Library/Preferences/SystemConfiguration/ and then reboot your machine.
• Reset your Mac’s System Management Controller (SMC)- For doing this first turn off your iMac, disconnect the power and hold down the Power Key for 5 seconds and release the button. When you are done with the same then Reattach the power cables and boot the Mac as usual.