I have an iMac OS X Version 10.4.11. Can I download any new version with this?
Choose About this Mac from the Apple menu and check the processor.
If it's a G3, no further upgrades are available.
If it's a G4 or G5, buy a retail Mac OS X 10.5 DVD from a source such as Amazon or eBay; Apple still might have copies in stock if you phone them.
If it's an Intel Mac, buy a Mac OS X 10.6 DVD from the online Apple Store.
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