I have iWork'09 running on a 27" iMac with Lion, but can't get it installed on my 21" iMac. I tried two different DVDs fgor installation.
Don't forget to run Software Update. The iWork apps on the DVD are versions that must be updated to run on Lion or Mountain Lion.
This helped, but after the update, my Mac thinks this is a "demo" version. I tried entering what seems to be a tiny serial number on the package, but nothing worked. I tried registering iWork. I will see what that brings.
You must still have a trial copy on your system. If you run the uninstall script on this page and then reinstall from the DVD you should be ok.
Thank you very much
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