I'd stay away from iWork and even sell your mac if at all possible if your not going to be an audio engineer like myself. Windows is much better at productivity then Apple at the moment and Word, Powerpoint, and Excel are accessible for a host of screen reading solutions like NVDA, Jaws or Window Eyes, as well as System Access. The biggest difference between the two suites is that you can only download the iWork desktop apps on an Apple device. While you can use Office on a Mac, you cannot use iWork on a Windows machine. I found a workaround that worked for me, at least. Uninstall the new versions of iWork, reboot and then reopen the iWork '09 versions that are still on your computer (at least they were on mine). Keep the iWork 09 apps open and go to the Mac App Store and download the new versions again. IWork for iPhone and iPad is Apple's mobile office and productivity suite, comprised of Pages for word processing, Numbers for spreadsheets, and Keynote for presentations. The iWork suit of apps is similar in features to what Microsoft offers with their Office for iPad suite of apps. Mar 23, 2021 Apple Updates iWork Apps for iOS and macOS to Version 11 Tuesday March 23, 2021 10:21 am PDT by Juli Clover Apple today updated its suite of iWork apps designed for iOS and macOS devices to version.
I cannot duplicate this here with Pages '09 v4.3, Pages 5.6.2, or Pages v6.1 (Sierra 10.12.4). PDF are always replaced without aberrant behavior by any version of Pages. As you have discovered, deleting/reinstalling Pages has no bearing on the problem. Which explicit version of Pages are you using and on what version of macOS?
Reboot your mac in Safe Boot mode. Try overwriting a PDF in this mode. Any change? Reboot normally, and repeat overwriting a PDF to see if the problem is solved.
What Is Apple Iwork
Apr 18, 2017 7:34 AM