Try rebotting the machine
Quit all iWork applications
navigate to the "Library" for the problem user account by selecting the menu item (in the Finder) "Go > Go To Folder..."
then enter "~/Library/Preferences/"
now locate the files:
And move them to the desktop
now start Numbers again.
If it launches then trash all of the files listed above (not if you only want to deal with Numbers filter the above list to just files that are "...com.apple.iWork.Numbers..."
NO JOY! I tried this per previous posts from way back. Cleaning up the "Preferences" files makes no difference. There are four accounts on this iMac. I determined that Numbers and Pages only works on one of them (?!?). For the non-working accounts, these apps never start, it's just the spinning beach ball. As a result, most of the files don't even exist for the account.
The only files I messed with are the "*.plist" files. I removed and reinstalled the apps, but I did not mess with any specific files.
Hmmm? Being an ol' Windows guy, I was very impressed with the iMac up until now. Some folks have been advocating the Office for Mac; rumor has it the iWorks apps are buggie. I don't have time for that. Any thoughts?
When you installed and removed and reinstalled the apps, were you logged in to the original administrator account that was first set up when you originally set the computer up?
Is the one account that does work the one to which you were logged in when you purchased the apps, and might that account not be an administrator account? (Are the apps in the computer's Application folder, or are they in an application folder under a particular user?)
Thank you all for your support and responses. It all helped!
While exploring various forums and chat sites I discovered two things: First, if I turned off iCloud the iWorks apps worked fine, specifically if I turned off Documents and Data; second, after changing iCloud settings and logging off, I discovered the settings unchanged when logging back in. Another post mentioned the permissions associated with the User Library folders and their children. Similar to what Jeff mentioned above, I had changed the Administrator setting for other accounts between installing Pages and Numbers. I suspected that the Library folders were not allowing the user accounts to modify various files; so I changed the permissions on the User Library folders such that the user and admin (me) had read & write for all the content. That fixed everything: Changes to settings stick and the iWorks apps are functioning. The whole iMac is a bit snappier, too. I suspect my admin change had things pretty hosed up.