Outlook 2016 Preview after Upgrade

[MKElectric 0]

I recently upgraded from Nitro Pro 10 to 12.  After doing this, I'm no longer able to preview PDF attachments in Outlook.  It says there is "No previewer available."  I was able to get previews by making Acrobat Reader DC my default PDF program.  But, obviously, I don't want Acrobat Reader to be my default PDF program.

How can I keep Nitro Pro 12 as my default PDF program and get the previews to come back?

[Leslie V. 0]

Hello @MKElectric,

Thank you for posting on our Community Forums!

I would like you to try the following:

1. Run a repair on Nitro Pro. 
2. Re-register the DLL file using the following Administrator command (Admin CMD): 

For a 32-bit computer
regsvr32 -u "C:\Program Files (x86)\Nitro\Pro 12\NitroPDFPreviewHandler.dll" 
regsvr32 "C:\Program Files (x86)\Nitro\Pro 12\NitroPDFPreviewHandler.dll" 

For a 64-bit computer
regsvr32 -u "C:\Program Files\Nitro\Pro 12\NitroPDFPreviewHandler.dll" 
regsvr32 "C:\Program Files\Nitro\Pro 12\NitroPDFPreviewHandler.dll" 

I hope that helps!