1. Run ‘Repair System Permissions‘ in Disk Utility.
Repairing system level permissions won’t solve the kext cache problem, but you’ll want to make sure they are all in order first. There is no need to repair ACL permissions for this procedure.
2. Open Terminal.app
Copy and paste the following:
sudo chown root:admin /
Hit ‘return’ and type in your admin password. This step ensures that the admin user has ownership permissions for everything on the startup disk.
3. Fix the kext cache permissions
Paste the following code into Terminal.app, hitting ‘return’ again and supplying the password if requested (if you do this shortly after step 2 you may not be asked for the password again):
sudo touch /System/Library/Extensions
4. Clear Console log and restart
The next two steps aren’t strictly necessary, but are good practice. Open Console.app, click ‘All Messages’ in the sidebar and hit the ‘Clear Display’ button in the Tool bar. Now, restart your mac.
5. Check for the problem
See if the procedure was successful by opening Console.app again, choosing ‘All messages’ in the sidebar and typing
in the filter/search bar over on the right. If you carried out the procedure above correctly, it shouldn’t return any ‘can’t create kext cache / user isn’t root’ messages since the restart time.
Featured picture: I’m not a balloon owner anymore by ~starwink
If you find deleting a file deletes it immediately without sending it to the Trash first, you may need to fix permisssions on your Trash folder.
Open Terminal (Applications > Utilities > Terminal.app) and type
Scroll up if necessary to the beginning of the list and you should see a couple of folders whose names begin with a dot.
Ignore .Trashes, but look at the permissions on .Trash, they should read like this (also see the pic above):
drwx- – – – – – <your_username> staff (size) (date) .Trash/
Ignore the numbers, but if the permissions are different or the username is not your account username, then do the following:
At the Terminal command prompt, type the following, replacing ‘your_username’ with (yep, you guessed it…) your username.
sudo chown -R your_username .Trash
For example, if my user name is ‘SnowLpd’ I would type
sudo chown -R SnowLpd .Trash
Then press ‘Return’. You will need to enter your password, which will be invisible when you type it (so type carefully). Now go and test your ‘delete’ function to see if the problem is cured. 🙂
UPDATE: Please also see How To Troubleshoot Your Mac with FT2.
There can be various reasons why your Mac starts running slowly. Some of these can be app-related – especially if you are making multiple changes in programs that have autosave enabled. Other problems could be due to running processor-heavy apps that need more RAM than you’ve presently got. Before you dash off to Crucial to check out your RAM upgrade options, here’s a few basics to run through:
1. Applications > Utilities > Disk Utility.app
How old is your HDD drive? Click on the top-most hard disk icon in the left column and check the S.M.A.R.T status at the bottom right of the window. Does it say ‘verified’? If it says anything else, back up all your important data and start thinking about buying a new hard disk. If the S.M.A.R.T status is verified, have a look at how much space you’ve got left. A nearly-full disk will slow you down. Generally, it is recommended that you have at least 10% free, but I’d work on getting that closer to 25% for optimum performance. If you have less than that, think about what can be archived onto a backup disk (or two..), such as photos, movies, and even your songs.
2. Applications > Utilities > Activity Monitor.app
What’s using all the CPU time? Is it something you need to be running? Select any obviously unnecessary resource hogs and hit ‘Quit Process’.
3. > System Preferences > Users & Groups
How many apps are in your ‘Login Items’? Remove anything that is not absolutely necessary at start up time.
4. Have you downloaded MacKeeper or other Anti-virus software?
If so, remove it.
5. How recently did you upgrade to Lion and are you using Time Machine?
If you’ve only recently upgraded in the last day or so, or turned your Mac off not long after upgrading, perhaps Spotlight is still indexing (indicated by a dot in the middle of the ‘spyglass’, top right of your screen) or TM is still updating (indicated by the TM indicator spinning in the menubar). Either or these will eventually finish and return your system to (about) normal, but you should let your system run (leaving it in ‘Sleep’ mode will do the trick) for at least 24 hours if you’ve only just upgraded.
6. Did you repair system permissions after upgrading?
Even though the Lion installer should fix system permissions after an upgrade, if you then added any other 3-rd party apps or restore something from Time Machine, repairing permissions is always a good idea. Doing so is harmless, and rules out permissions as a possible factor of poor performance. Do Step 4 here. Unless any are indicted in red type, don’t panic about the permissions errors that come up in the ‘details’ window – many of these can be safely ignored.
7. Clear out your caches
Caches, in general, help to speed your computer up. However, if you’re a heavy internet browser and you’ve never cleared your caches or your history (I mean like in several months), then this is worth doing from time to time. You can clean out Internet caches in Safari or Firefox by choosing Safari > Empty Cache or Firefox > Tools > Clear Recent History > Everything. Your computer has other caches that can usefully be cleared out periodically, too: use OnyX to do so.
8. Is the system slow with just one particular program or while trying to open some particular window?
A couple of things could be going on here. If its your browser, try killing some of those extensions/add-ons – every one of them slows you down just that little bit, and many slow you down a lot. Another possibility is a corrupt ‘plist’ or preference file associated with a particular app. Curing this is a bit more tricky and requires knowing your way around the hidden Library folder. If you think this is your problem, leave a comment below to get further instructions.
featured picture Speedo ©2011 Phil Stokes
why is my mac running so hot?
FastTasks – download the free OS X utility app from Applehelpwriter
(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
1. FileVault is turned on
Solution: either turn FileVault off, or put up with the behaviour.
2. If you are using an account with ‘Parental Controls’ enabled, the person who set up your account may have denied you permission to delete, modify or move some or all files.
Solution: Speak to mom!
If 1 and 2, aren’t your problem, then you may have some permissions errors.
3. Check Permissions on .Trash
— 1. Open a Terminal window (Applications >Utilities > Terminal.app) and check the permissions by typing/pasting in the following:
You should end up with a long list, among which will be the permissions for your .Trash folder. Mine looks like this:
drwx—— 2 SnowLpd staff 68 29 Nov 15:33 .Trash
— 2. What’s important here that the name after the series of ‘drwx’ letters is the same as your user name (my user name, as you can see, is ‘SnowLpd’). If it is, then ignore the rest of this post and go to the post Permissions Pt2.
If the name is not the same, then you need to type this command into Terminal:
sudo chown -R your_username .Trash
Where you replace your_username with (surprise…) your user name, which is also the name of your home folder (note there’s a space both before and after your_username). Thus, for example, if in the previous step it said ‘root’ instead of my username, then I’d type in ‘sudo chown -R SnowLpd .Trash’.
—3. Now press ‘Return’. You will be prompted for your admin password. Type it in, but notice that you won’t see anything as you type, so type carefully. Hit ‘Return’ again. You should be returned to the Terminal prompt pretty quickly. Quit Terminal.app and see if your problems are solved.
4. If your .Trash permissions were OK, then you may need to fix either system permissions or ACL permissions. To do that, go to the next post.
how to fix permissions (Permissions Pt 2)
‘delete’ doesn’t send files to Trash