The other day I had the opportunity to troubleshoot two issues on an iMac using iChat’s Screen Sharing feature. While the screen sharing itself isn’t new, it’s been around for ages via various VNC software and was made easier in Mac OS X when Leopard came out in 2007, the actual use of it makes you feel like you’re working in the future.
iMac can’t boot properly
The first problem was that the iMac wouldn’t boot into the system. It would display the Apple logo and just stays there for hours. This is unsolvable using screen sharing since the iMac wouldn’t boot so we went via text chat.
Get the original Install DVD from the box the iMac came in. If you don’t have this DVD or something similar, you’re basically screwed until you can get yourself one or you go to an Apple Service Provider to fix your problem.. Don’t lose this DVD. If you do, you need to have a Mac OS X Leopard or Snow Leopard DVD that you can buy from any Apple Reseller.
Insert the DVD, follow along as if you were to install the OS but once you see the menu bar on top, select Utilities from the menu bar and choose Disk Utility. Select the hard drive of the Mac and choose Repair Permissions. Once it’s done, it doesn’t hurt to click on Repair Disk.
Once you do that, restart the computer.
If the hard drive is not detected by Disk Utility then your problem is more serious than that. You need to take it to an Apple Service Provider.
Locked Time Machine drive
The second problem I faced while troubleshooting that iMac was that it had a Time machine backup drive, presumably a Time Capsule, which was inaccessible.
Once the iMac restarted successfully, the backup drive appeared with a padlock image on its icon indicating that the user account is unable to access it. It turns out none of the administrator account could access that drive.
1. Open Terminal
2. Enter the following lines:
sudo chflags nouchg /Volumes/“TM drive name”
followed by
sudo chmod 775 /Volumes/“TM drive name”
This command needs a password.
Note that you have to have a password set for an administrator account. When you enter the first command, you’ll be prompted for a password. This is the password for the administrator account. If you set up your account without a password, go to System Preferences > Accounts > and change the password. You can replace the password with a blank one after this is done if you don’t want to use one.
How do you know you use or have an administrator account? Go to the Accounts pane in System Preferences and see the label underneath your account name.