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problems with wifi, Safari and Mountain Lion
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
http://osxdaily.com/2012/08/02/fix-os-x-mountain-lion-wireless-connection-problems/
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
/Applications/Utilities/Terminal.app
and paste this command
rm ~/Library/Preferences/com.apple.systempreferences.plist
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
how to secure your mac (OS X Lion)
Security in OS X Lion is a big problem that not many people are aware of, and here’s why: your Lion computer contains the install/recovery disk on the internal drive. That means anyone with a basic knowledge of Mac and Lion can start up your mac and reset your passwords, thereby accessing your user accounts and all your personal data. The same trick can help kids easily get round restrictions applied through OS X’s ‘Parental Controls’ feature.
How is this possible, you may ask? First, a little history. Among the 250 changes vaunted about Lion over its predecessor, Snow Leopard, there is one that is widely known but whose implications are rarely pointed out: you download the OS rather than install it from a disc. In the past, if your OS went bad and needed to be recovered, or you forgot your admin passwords, the simplest answer was to insert your install disk. From that, you could restore the OS and reset your passwords. That made your Mac a little safer (though not entirely safe) so long as your disc was kept somewhere physically different from your computer.
With Lion having no install disc, Apple had to find an answer as to how to provide the recovery option. The solution was to install a Recovery partition on the same disk as the operating system itself. In the event that the OS goes bottoms up and needs to be recovered or re-installed, you just restart your computer holding down the ‘command’ and ‘r’ keys to access the Recovery partition.
So far so good, but likewise, just as with the old DVD install discs, you — or anyone else — can also reset the user account passwords from the Recovery partition. That means your passwords are effectively useless. Anyone who wants to hack your user account just has to restart your Mac holding down ‘command’ and ‘r’ and then use the built-in Password Utility to make new passwords for your accounts. Now I’m not going to tell you quite how to do it (you do need a little knowledge to get the user account names and know how to do the reset) but it is widely publicized elsewhere, and indeed even in Apple’s own online documentation (so if you really want to know, google is your friend or follow some of the links in this post…).
What’s the answer to this security nightmare? Here’s one thing that’s NOT the answer but which I have seen widely touted: setting a firmware password. If you’re not familiar with the concept of the firmware password, don’t worry. It is practically useless, since anyone can reset that simply by taking off the back of your computer, and then pulling out and then putting back in one of the memory chips.
Apple, of course, thought about this problem. Their own solution is to encourage you to use FileVault 2 (FV2) to encrypt all your data. Indeed, this is the BEST solution. Without your password, no one can access the disk on your computer no matter what they do (and that includes YOU if you forget it…). However, there are a couple of drawbacks to FV2. One is that it requires extra disk space, and if you have more than one partition on your hard drive, or a lot of data, and little space you may not be able to encrypt and decrypt your data. The other drawback is that FV2 places a little extra wear-and-tear on your hard disk (though that may be negligible given the security pay off).
Using FileVault 2 is really the only security option if you’re using Lion. However, if you don’t have the space for it, there is a ‘second-best’ strategy (see below why it’s only ‘second best’), and that is to remove the recovery disk and use a clone as your recovery option instead (WARNING: the Recovery disk is required for FileVault 2, so by removing it you will also remove the ability to use FV2).
There’s a couple of ways to remove the recovery partition on your internal disk, but this is probably the best:
1. Clone your current system to an external disk using Carbon Copy Cloner. This will clone your entire system exactly as it is now, but it will not copy the Recovery disk.
2. Still booted into your internal OS (the one on your machine), open Terminal.app and paste the following command:
defaults write com.apple.DiskUtility DUDebugMenuEnabled 1
Press ‘Return’.
3. Open Disk Utility.app (Applications/Utilities/Disk Utility.app). In the menu bar of Disk Utility, choose Debug > Show Every Partition.
4. In the left-hand pane of Disk Utility, you can now see the Recovery HD. Click on it. Then click on the Erase tab on the (larger) right-hand pane. Click the Erase button down there on the bottom right.
5. Quit Disk Utility.
Now you can use your bootable clone as your recovery disk if your OS becomes corrupt and no one can boot up your computer with ‘command-r’. If you keep the clone backed up on a regular incremental schedule (you can choose anything from once an hour, once a day, week, or month), you can simply restore a corrupted internal disk to exactly the same state as your last backup.
Why only ‘second best’?
As alluded to earlier, it is still possible for advanced users to start up your mac and reset the password without the Recovery partition (this was also true in Snow Leopard even without the install disc). In fact, what this procedure does is give your OS X Lion installation the same security level as an OS X Snow Leopard installation, which is not actually that great, but better than Lion with a Recovery disk! Also, if you are storing highly sensitive data, don’t neglect the fact that someone who has complete unfettered access to your hard drive could even remove the disk and recover the data using special software.
The short story is if you want to be absolutely certain that your data is secure, FileVault 2 is really your only option.
featured picture Security Workstation by digitalhadz
how to unfreeze your iPad
iPads are so easy to use, why bother with the manual? 😉 The chances are though, that at some point you’re either going to find that an app freezes on your screen or your whole tablet becomes unresponsive. Don’t panic, the answer’s simple:
First, be sure that it’s connected to a power source. The most common reason for iPads not working is people don’t realise they’re out of battery! Otherwise try these:
If it’s just a particular App that’s frozen on your screen:
— Hold down the ‘sleep/wake’ button (top right, back edge) for about 5 seconds until the slider appears. Release the ‘sleep/wake’ button. Now hold down the ‘Home’ button (bottom front, centre) until you see your Home screen.
If your whole machine is unresponsive, then do a restart:
— Hold down the ‘sleep/wake’ button for about 5 seconds until the slider appears. Slide it to ‘Off’. Then hold it down again until the Apple logo appears showing that the iPad is restarting.
If that doesn’t work, do a hard reset:
— Hold down the ‘sleep/wake’ button AND the ‘Home’ button simultaneously for about 10 seconds or until the Apple logo appears.
*For more serious problems with your iPad, such as continual restarting or no home screen, have a look here.
featured picture: ice crystals by Typen