A spe­cial guest post­ing from Scott Theede:

Have you ever been exper­i­ment­ing with iWork (Pages, Num­bers, Keynote) and your free trial has run out leav­ing you unable to make any changes to your documents?

There’s a quick way to get around that restric­tion, say if you needed to have a fully func­tional keynote for an extra day of free trial for that impor­tant presentation.

Head to your hard­drive direc­tory, in my case Mac­in­tosh HD, then go to Library, then to Pref­er­ences, then look for the file com.apple.iWork09.plist (also works for iWork0X.plist, depend­ing on which trial ver­sion you are running)

Mac­in­tosh HD -> Library -> Pref­er­ences -> com.apple.iWork09.plist

Then sim­ply delete the file. Open up any of your iWork apps and with you can start a new 30 day trial.

I do not con­done doing this end­lessly; how­ever, it’s very use­ful in those instances when you need some extra time.