PDF preview using Windows EXplorer

Hi MarcASI, thanks for reaching out to us. 

Could you send me a screenshot (without any personal information) of what you're seeing, so that I can have a better visual understanding of this?

Could you also let me know if this .pdf file is Smart Synced as online-only or local, when you try to preview it?

Looking forward to hearing back from you!

If i click to preview an item that is not synced It will show a preview of the PDF.  if i then click somewhere else, that file becomes synced.  if i click a synced file i get no preview.  image below file ending in 00001 is a file i have previewed before, 00002 is a file i have not previewed before.  The 00002 does show a preview, for now.  as soon as i click elsewhere and click back that preview is gone, and it will sync for me automatically.

I can confirm I've seen the same issue on two separate machines the past week.

All files are online-only and when I click one, it previews normally. It downloads the file and changes the file to a green tick (locally stored, selective sync). After the file has been stored locally with the green tick, it will no longer be previewable. The preview pane is blank. If I copy-paste it to a different folder however (documents, downloads, etc), it previews fine.

The only workaround I've found is to right-click the file/folder, select Smart Sync and change it back to an online-only file. This however only works once as once you click it again it will download itself again and store it locally, cycling the problem.
Is there anything else we can try here?

Hi there, could you try reinstalling the Dropbox desktop application to see if this helps? Is your Windows device fully updated on all security patches and so on?

All patches installed.  Tried reinstalling dropbox.  No affect.

Does this behavior only occur in the Dropbox folder, or on any other folder on your machine?

It only occurs for dropbox folders.  I can copy a file that is either unsynced or synced and not showing a preview.  And paste it in another non-dropbox folder.  In the new folder the preview will show in either case.

Thanks for confirming that for us, MarcASI.

Could you also try the following steps in the exact order listed? Maybe they will do the trick.

• Go to the Dropbox icon in your system tray.
• Select the avatar icon on the top right corner of your Notifications panel.
• Choose Preferences...
• Navigate to the Account tab.
• Click anywhere in the window under the tab.
• Hold down the 'Alt+H' keys.
• Click on the Fix Hardlinks button.

If you're asked for your computer's login credentials, enter them, and then wait a bit to see if Dropbox resumes syncing.

If you don't see any improvement in behavior, try the same steps again, but this time, click on the Fix Permissions button. 

Let us know how it goes, cheers!

So not only did this solution not work.  It made things worse for a day.

It no longer shows the icons for what is synced and what is not synced which was very useful.  I have been using smart sync and liked those icons.  No previews for any file.  It seems to have reverted back after about 24 hours.

I have same issue, When I have a PDF file in the cloud and I click on it, it show a perview in explore and at the same time, downloads the file to my computer.  Once file is download, there is no longer a preview for the file.   I check the process is non dropbox folders and there is a a perview.  Only in dropbox folder once file downloads is there no preview.