Check if every setting is in place. Go to the following place "C:\Program Files (x86)\Foxit Software\Foxit Reader\Shell Extensions" or "C:\Program Files (x86)\Foxit Software\Foxit PhantomPDF\Shell Extensions" to check if the required DLL and EXE shown below are installed.
If there are files shown as above, then they are installed. Please exit Foxit program and any running File Explorer windows, do the following:
1. Open Windows Command Prompt, type
regsvr32.exe "C:\Program Files (x86)\Foxit Software\Foxit PhantomPDF\Shell Extensions\FoxitThumbnailHndlr_x64.dll"
regsvr32.exe "C:\Program Files (x86)\Foxit Software\Foxit PhantomPDF\Shell Extensions\FoxitThumbnailHndlr.dll"
2. Press Enter, if succeed, you will see the following message, click on Ok to finish it.
3. Open a File Explorer window see if the preview works this time.
If not, check the following:
1. In the Windows File Explorer, open the Folder Options, see if the option Always show icons, never thumbnails option is un-checked , and the option Show preview handlers in preview pane is checked.
2.In the Windows File Explorer, change the view layout to Medium or Large icons.
If the above items are ok and preview still fails, write to support by including the following information:
1) Descriptions together with screen captures to show how the preview not works.
2) What you have done in order to make it work.
3) What’s your operation system information, like Win 10 64 bit.
4) What program and version type of Foxit you are having.