Any luck with this? I've tried the suggestions in doing online repairs, uninstall/reinstall, nothing seems to work? S4B 2016 w/ all updates, plugin version 7.3.0.308.
Tried running procmon.exe from SysInternals to track the error and don't see much out of the ordinary other than it first looks for the Mitel DLL's in C:\assembly, then eventually finds them in the Program Files\Mitel folder.