What year, screen size, CPU speed and amount of RAM installed?
To find out info about your system,
Click on the Apple symbol in the upper left of the OS X main menu bar. A drop down menu appears.
Click About this Mac. A smaller popup window appears. This gives you basic info like what version of OS X your iMac is running, the speed of your iMac's CPU and how much RAM is installed.
Click on the button that says More Info. A larger window appears giving you a complete overview of your iMac's hardware specs.
Highlight all of this info and copy/paste all of this into another reply to this post, editing out your iMac's serial number before actually posting the reply.
This will tell us everything about your iMac so we may begin to help with your iMac issues.
My station is unable to validate Mac OS X Upd Combo 10.5.8. Any ideas out there on how to remedy this?
Model Name: iMac
Model Identifier: iMac7,1
Processor Name: Intel Core 2 Duo
Processor Speed: 2 GHz
Number Of Processors: 1
Total Number Of Cores: 2
L2 Cache: 4 MB
Memory: 2 GB
Bus Speed: 800 MHz
Boot ROM Version: IM71.007A.B03
SMC Version: 1.20f4
Instead of trying to download and install the 10.5.8 combo update ( as I believe that this update may no longer be on Apple's servers) you can just "upgrade" your iMac to OS X 10.6 Snow Leopard. found here.
Before purchasing and upgrading to a new OS X version, it would be prudent to make sure to have a viable backup of your current system and all your important data.
You can backup your system by purchasing and connecting and formatting an external hard drive ( I prefer powered hard drives that have their own dedicated power supply) that can be a USB 2.0 or FireWire 800 connected hard drive (I prefer FireWire 800 hard drives as the as faster hard drives, but more expensive).
You use can use your current OS X Disk Utility App version to format the external hard drive as a OS X Extended Format with GUID partition scheme.
Then purchase and install a data cloning app like CarbonCopyCloner or SuperDuper to create an exact and bootable clone/copy of your Mac's internal hard drive system to the external hard drive.
Once you have a viable backup of your current system, you are ready and can install the OS X 10.6 Snow Leopard DVD.
Once OS X 10.6 Snow Leopard is installled, you can use OS X Software Update feature (located in the OS X System Preferences Panel) to update your OS X 10.6 system to OS X 10.6.8 Snow Leopard.
By updating your system to OS X 10.6 Snow Leoaprd to OS X 10.6.8, you now have access to Apple's Mac App Store.
You can then decide from this point whether or not you want to leave your Mac running OS X 10.6.8 OR "Upgrade"your Mac, again, to the free OS X 10.9.2 Mavericks.
If you decide that you might want to "Upgrade" your Mac one more time to OS X Mavericks, be advised that you need to increase the amount of RAM installed in your Mac.
OS X 10.9 Mavericks mimimum RAM requirement is 2 GBs , but the real world "working minimum of RAM is 4 GBs or greater.
Your year and model Mac can take a total of 6 GBs of RAM, max.
I would, STRONGLY, advise installing the total 6 GBs of RAM before deciding to upgrade your Mac to OS X 10.9.2 Mavericks.
Correct and reliable Mac RAM can be purchased from online Mac RAM sources Crucial memory or OWC (macsales.com).
OWC (macsales.com) is the only Online Mac RAM vendor that has the 6 GB RAM kit.
RAM is completely user installable and is, relatively, easy to install by the user.
Also, I forgot to mention that if you have a lot of older software that was a carry over from older PowerPC Macs, this software will no longer function on the newer versions of OS X like OS X 10.7 Lion, OS X 10.8 Mourain Lion and OS X 10.9 Mavericks.
This older software will continue to function in OS X 10.6 Snow Leopard.
Good Luck to you!
In case you want to stay with leopard (the 10.5.8 combo update is still available from Apple):
Some general advice on updating Leopard:
It is worth noting that it is an extreme rarity for updates to cause upsets to your system, as they have all been extensively beta-tested, but they may well reveal pre-existing ones, particularly those of which you may have been unaware. If you are actually aware of any glitches, make sure they are fixed before proceeding further.
So before you do anything else:
If you can, make a full backup first to an external hard disk. Ideally you should always have a bootable clone of your system that enables you to revert to the previous pre-update state.
Turn off sleep mode for both screen and hard disk.
Disconnect all peripherals except your keyboard and mouse.
1. Repair Permissions (in Disk Utility)
2. Verify the state of your hard disk using Disk Utility. If any faults are reported, restart from your install disk (holding down the C key), go to Disk Utility, and repair your startup disk. Restart again to get back to your startup disk.
At least you can now be reasonably certain that your system does not contain any obvious faults that might cause an update/upgrade to fail.
3. Download the correct version of the COMBO update from the Apple download site.
The Combo updater of Leopard 10.5.8 can be found here:
If you prefer to download updates via Software Update in the Apple menu (which would ensure that the correct version for your Mac was being downloaded), it is not recommended to allow SU to install major (or even minor) updates automatically. Set Software Update to just download the updater without immediately installing it. There is always the possibility that the combined download and install (which can be a lengthy process) might be interrupted by a power outage or your cat walking across the keyboard, and an interrupted install will almost certainly cause havoc. Once it is downloaded, you can install at a time that suits you. You should make a backup copy of the updater on a CD in case you ever need a reinstall.
Full details about the 10.5.8 update here: http://support.apple.com/kb/HT3606
More information on using Software Updater here:
Using the Combo updater ensures that all system files changed since the original 10.5.0 are included, and any that may have been missed out or subsequently damaged will be repaired. The Delta updater, although a temptingly smaller download, only takes you from the previous version to the new one, i.e. for example from 10.5.7 to 10.5.8. Software Update will generally download the Delta updater only. The preferable Combo updater needs to be downloaded from Apple's download site.
Now proceed as follows:
4. Close all applications and turn off energy saving and screensaver.
5. Unplug all peripherals except your keyboard and mouse.
6. Install the update/upgrade. Do not under any circumstances interrupt this procedure. Do not do anything else on your computer while it is installing. Be patient.
7. When it ask for a restart to complete the installation, click restart. This can take longer than normal, there are probably thousands of files to overwrite and place in the correct location. Do nothing while this is going on.
8. Once your Mac is awake, repair permissions again, and you should be good to go!
If your Mac seems slightly sluggish or ‘different’, perform a second restart. It can’t hurt and is sometimes efficacious! In fact a second restart can be recommended.
9. Open a few of your most used applications and check that all is OK. In this connection please remember that not all manufacturers of third party applications and plug-ins, add-ons, haxies etc, will have had time to do any necessary rewrites to their software to make them compliant with the latest version of your operating system. Give them a week or two while you regularly check their websites for updates.
N.B. Do not attempt to install two different updates at the same time as each may have different routines and requirements. Follow the above recommendations for each update in turn.
Lastly, Apple's own article on the subject of Software Update may also be useful reading:
[b]If you are updating Safari (or just have):[/b]
Input Managers from third parties can do as much harm as good. They use a security loophole to reach right into your applications' code and change that code as the application starts up. If you have installed an OS update and Safari is crashing, the very [i]first[/i] thing to do is clear out your InputManagers folders (both in your own Library and in the top-level /Library), log out and log back in, and try again.
So, disable all third party add-ons before updating Safari, as they may not have been updated yet for the new version. Add them back one by one. If something goes awry, remove it again and check on the software manufacturer's website for news of an update to match your version of Safari.
Most errors reported here after an update are due to an unrepaired or undetected inherent fault in the system, and/or a third party add-on.
Additional tips on software installation here:
To reiterate, Input Managers reach right into an application and alter its code. This puts the behavior of the affected application outside the control and responsibility of its developers: a recipe for problems. That's not to say that issues absolutely will ensue as a result of Input Managers, but you, as a user, must decide. If the functionality of a specific Input Manager or set thereof is really important to you, you may well choose to assume the associated risk.
Again, the advice is to remove all Input Managers from the following directories:
especially prior to system updates (they can always be added back one-by-one later).
Solutions for troubleshooting installation, startup, and login issues in Mac OS X v10.5