If you’ve upgraded to Mountain Lion and traded swift wifi and fast Safari for a flakey internet connection and sluggish browser, you are not alone. Widespread reports of problems with wifi, Safari and Mountain Lion have been mounting ever since July 25th. However, unlike the lengthy debacle with similar wifi problems experienced after the Lion upgrade last year, a lot of users are finding their problems can be solved by using one or more of the tips below.
1. Create a new location and renew the DHCP lease
OS X Daily have a step-by-step procedure here
that is proving hugely successful. Don’t forget to follow their second step about changing the MTU value while you’re at it.
2. Reset default system preferences
If that didn’t do it for you, it’s time to roll up your sleeves and enter Terminal! Open the Terminal.app from
and paste this command
then press ‘return’.
You will need to restart your mac to see if this has had any beneficial effect, so do that now.
3. Do PRAM & SMC resets
If you’re still suffering problems, it’s time for a couple of system resets. To do the SMC reset you will need to see what kind of mac you have, as the procedure is different for some models. Take a look here and follow the instructions for your model.
Before powering up after the SMC reset, also take the trouble to do a PRAM reset. To do that:
i. Ensure the machine is powered off.
ii. Locate the following keys on your keyboard in preparation for Step 4:
‘command’ – ‘option’ – ‘P’ – ‘R’
iii. Press the ‘power on’ button.
iv. Immediately – and before the grey screen appears – hold down ‘command-option-P-R’ all together.
v. Keep them held down until you’ve heard the start-up chime twice. After you release them you should hear it again, and hopefully your Mac will boot up without wifi/Safari issues.
4. Check Wifi connection
And if that doesn’t work? Time to check your wifi connection. See how strong your signal-to-noise ratio is. You need something in the order of 25 or higher. To find out whether you signal is strong enough, hold down the ‘option’ key and click on the wifi icon in the menu bar. Choose Open Wifi Diagnostics from the menu.
When you see the welcome screen, ignore the ‘Continue’ button and instead press ‘command-N’ on your keyboard.
Click wifi scan in the task bar and scroll to the right where you will see two numbers, ‘signal’ and ‘noise’. Ignore the minus ‘-‘ signs, and subtract the signal number from the ‘noise’ number. Anything over 25 is a good enough signal, below that and the signal is too weak for a reliable connection. Over 40 is excellent (in the example below, you can see the SNR is 34, a pretty good signal for a home router located on the next floor).
If your SNR is lower than 25 you need to either move the computer closer to the router or find a better connection. If the ‘Noise’ shows a very low figure (equals more noise), you can try changing the channel on your router. Look at the other routers in the list and if they are using the same channel as yours, switch your router to something else between 1 and 11.
5. Reinstall OS X
If all else fails…some users are reporting that simply reinstalling OS X is solving the problem for them. Reinstalling doesn’t touch your Apps or user data, but its always wise to make sure you have a backup before undertaking such an operation.
To reinstall, restart the computer while also holding down ‘command-R’ on the keyboard. From the Utilities window that opens up, choose ‘Reinstall OS X’.
Still having problems? Let us know in the comments below.
featured picture: Internet by ~vagraine
(This post continues from here on file permission problems.)
Did you know there are two levels of permissions on your mac? User level and system level. Most discussions of fixing permissions only discuss the latter, but you may also need to fix the former (also sometimes called ‘ACLs’) for some problems caused by upgrading Lion on top of Snow Leopard.
4. System Level Permissions
You can safely repair your system level permissions at any time, and doing it once in a while is a good maintenance activity even if you’re not experiencing any problems. It’s also the first thing to do as soon as you notice any problems with apps launching, file access problems, or your computer seems to be running unusually slow.
How to do it:
— 1. Go to Applications > Utilities > Disk Utility.app and double click the app to open it.
— 2. Click your HDD icon in the left column (if you have more than one, click the one that contains your startup disk).
— 3. If it is not already selected, click on the ‘First Aid’ tab. Choose the ‘Repair Disk Permissions’ button near the bottom of the window (see the larger of the two windows in the screenshot above).
— 4. Wait for the process to finish (it could take ten minutes or more), then quit Disk Utility. You can ignore most of the error messages that appear unless they’re in red.
5. User Level Permissions (ACLs)
These permissions apply only to your ‘Home’ folder and its contents, and if you have more than one user you will need to do this procedure for any user experiencing a problem. However, unlike system level permissions, repairing ACLs isn’t something you should do unless there is a specific issue to be solved. Problems that this repair might help with include permission conflicts inherited from an earlier Snow Leopard or Leopard installation, such as Finder always asking for your password when you try to delete, move or copy a file.
To reset the ACLs in Lion: (To reset the ACLs in Leopard/Snow Leopard have a look here.)
— 1. Remove the current ACLs by opening Terminal.app (Applications > Utilities > Terminal.app) and copy and pasting this command:
sudo chmod -RN ~
Press return. You’ll be asked for your password. Notice that when you type it in you won’t see anything on the screen. Press return again. If you get an error message, you probably didn’t type in your password correctly. Repeat this step till its accepted. It will take some time to complete. Then paste this command into Terminal also:
sudo chown -R `id -un` ~
and press return. Enter your password again if necessary.
— 2. Press the Power button on the computer and choose ‘Restart’. When the screen goes blank, hold down the ‘command’ and ‘R’ keys on the keyboard until you hear the start up chime. In the menu bar at the top, choose Utilities > Terminal
— 3. At the Terminal prompt type
Then hit ‘Return’
— 4. Forget about resetting your password; what you’re looking for is your hard disk icon at the top. Hit that, and then from the drop-down menu select your user account.
— 5. Go to the bottom of the dialogue window – leaving all password fields blank – and choose ‘Reset’ under ‘Reset Home Folder Permissions and ACLs’ (see the smaller of the two windows in the screenshot above, inside the red dotted line).
— 6. When the process finishes, quit everything and restart your Mac. 🙂
How to Troubleshoot Your Mac with FT2
can’t create kext cache error
FastTasks – download the free OS X utility app from Applehelpwriter