When clicking on File/Share/E-mail, Outlook opens instead of Thunderbird, even when Mozilla Thunderbird is set to the default e-mail client, and wants to send PDFs by mail via Thunderbird.
Power PDF is looking for the following registry hive “HKLM\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\App Paths\OUTLOOK.exe”.
So, as long as this registry entry is on the system, Power PDF will try to launch Outlook, regardless of what email client is installed and/or set as the default mail application in Windows.
This seems to be hard coded into Power PDF, and cannot be changed. However, I have found 2 workarounds other than uninstalling Outlook that have worked on a test system.
The following will prevent Outlook from being used.
Rename “C:\Program Files\Microsoft Office\root\Office16\OUTLOOK.EXE” to “C:\Program Files\Microsoft Office\root\Office16\OUTLOOK.EXE.old”
The following will allow Outlook to be used, but will allow Power PDF to use the default email client.
Rename the following registry hive from: