Preview edits PDF not saved

Hello Mark-Pat-Joe-Bill-Dinosaur, 

Thank you for posting in the Apple Support Communities. I understand you are having problems saving edits to PDF documents.

"Preview automatically saves changes for you as you work, so you don’t have to explicitly save your changes. You might want to explicitly save a document if you want to, for example, save a copy of the document in a different location.

Preview periodically saves “snapshots” of your document, called versions, so that you can revisit the document as it appeared in the past and revert to a previous version. When you’re actively editing a document, Preview saves a version at least every hour, and more often if you’re making significant changes. Preview also saves a version when you open a document, save or duplicate a document, lock or rename a document, or revert to a previous version."

“Explicitly save a Preview document

1. In the Preview app on your Mac, open a PDF or image that you want to save.
2. Do any of the following:

• • If you make several edits to a document and you want to be sure you have a version with all of them, choose File > Save.
  • If you created a new document by choosing File > New from Clipboard, it’s saved automatically as you edit. When you’re ready to name the document and place it in a particular location, choose File > Save.
  • To save the document using a different filename, location, or format, hold down the Option key and choose File > Save As.

If you have iCloud set up and iCloud Drive turned on, you can save your documents in the Preview folder in iCloud Drive by clicking the Where pop-up menu, choosing “Preview — iCloud,” then clicking Save. See Use iCloud Drive to store documents.

Tip: You can also hold the pointer over the document title and click the arrow to save the document or change its location.”

You’ll find the steps above, and additional help in the article linked below.

• Manage versions of a Preview document on Mac

Have a good one!

Log into another user account and see if the problem persists there in Photos. (This tells us if the problem is limited to your user account or is system wide).

Boot into Safe Mode (Use Safe Mode to isoloate issues with your Mac and Playing Safe: what does Safe Mode do?) and test Preview's editing from there. Reboot normally and test again.

NOTE: Safe Mode boot can take up to 10 minutes as it's doing some system cache cleaning, volume verifying and directory repairing. 

Hi Mark-Pat-Joe-Bill-Dinosaur, 

It sounds like you have a firm grasp on using Preview to edit and save your PDF documents. From the information you’ve shared, it sounds like the issue is most likely related to the specific file you are working with. I’d suggest obtaining a new copy of it, and perhaps test saving it in a different location to test for the same behavior. 

Cheers!