64-bit Acrobat Reader not fully compatible with 32-bit Office on 64-bit Windows 10

[MichaelExFairlight]

I have 64-bit Windows 10 with 32-bit Office 2016 installed. The 32-bit reader worked fine on this machine for years.  But after an automatic upgrade to 64-bit reader, the PDF preview in Outlook no longer works, says there is no PDF previewer installed.  Inspection of Outlook settings confirms no PDF previewer available. It seems the only solution is to revert to 32-bit reader, but I cannot find any way to do that.  The installer uses the 64-bit version because the OS is 64-bits.  Is there a way to force installation of the 32-bit reader on 64-bit Windows 10? 

[Amal.]

Hi MichaelExFairlight 

Hope you are doing well and sorry for the trouble. As described the PDF preview in Outlook doesn't work and throwing the error 'there is no PDF previewer installed'

Would you mind sharing the build version of Win 10 you are using? If it is version 1909, please try to update the Windows to the latest build version (2004, 20H2 or 21H1) as described in the MS help page https://support.microsoft.com/en-us/windows/update-windows-10-3c5ae7fc-9fb6-9af1-1984-b5e0412c556a and reboot the computer once and see if that works for you.

Regards

Amal

[MichaelExFairlight]

Hi Amal 
I am using build 2004.  

I have already spent some time trying every suggestion I could find online, and chatting to Adobe support.  I even allowed one of them to share my desktop but after trying many things they could not find a solution and told me to revert to 32-bit reader.  However they did not know how to do that (!) and recommended I try this forum. 
I have inspected the registry and can see that Acrobat Reader is correctly setup as PDF previewer in 64-bit registry, but that is no use to 32-bit Outlook.  A 32-bit application cannot use a 64-bit DLL.  I should clarify that the 64-bit reader appears to be working fine in other regards, only the PDF Preview in Outlook is not working.  But that is a real drag!  

Regards, 
Michael

[Amal.]

Hi Michael

We are sorry to hear that. Please checkout the steps shared in the MS help page i have found for the similar issue and see if that works for you. https://social.technet.microsoft.com/wiki/contents/articles/53322.outlook-problem-with-pdf-preview-h...

Regards

Amal

[MichaelExFairlight]

Hi Amal

Thank you for continuing to help me with this! 
 I had already found that article, and it did not help. The article predates the release of 64-bit Reader and refers to a similar but different problem with 32-bit Reader in 64-bit Windows 10.  Nevertheless I reviewed the recommended steps.  
In Step 3 I cannot enable PDF Preview Handler as suggested because it's not there.  
In Step 4 the registry is already set exactly as described.  But this entry is in WOW6432Node and pertains to the 32-bit Reader. The 64-bit Reader has setup the 64-bit registry entry as shown below.  I presume that 64-bit Outlook would find this and work correctly. 

[MichaelExFairlight · Accepted solution]

This problem is resolved by the solution in https://community.adobe.com/t5/acrobat-reader-discussions/pdf-preview-handler-missing-in-outlook-365...