Launching Email from 3rd party app with Outlook 2016

We use a software product called Formdocs that does electronic forms for us.    In the past with Windows 7 and Outlook 2007 we could program an electronic form to launch an Outlook email and prefill the recipient(s).   With Windows 10 and Outlook 2016 this feature does not work.   We can launch a new email without pre-filling recipients, and that works fine.   It’s only when the software does the prefill.    Does anyone at RTM have any ideas on what might be the cause?    We tried uninstalling Trend Anti-virus and using Microsoft defender in thinking it might be the anti-virus but that didn’t help.
The runtime error we get from Formdocs is really unhelpful, and their support department just tells us the issue is with Windows or Outlook.   Not them.   They have never been very good support-wise.
Who is Participating?
Karl Timmermans (Outlook MVP)Connect With a Mentor PrincipalCommented:
Hate to state the obvious but if a vendor (any vendor) has

an issue integrating with another 3rd party program from any vendor, there generally two approaches to resolve the problem

#1 - Get the vendor having an issue to deal with the problem or
#2 - if they can't resolve it, they'll need to connect with the other vendor (Microsoft in this case)

Only the original vendor has the source code not to mention that  Outlook '2007 is no longer support  and definitely is not tested on Windows 10 so  this isn't a case of there being a problem with an MS program but FORMDOCS not taking the time/making the effort to keep their program current. The starting point starts with them to either find a work around or fix the problem  outright - they own their own code.
All Courses

From novice to tech pro — start learning today.