Exception EFOpenError in module


Dear support,
my user has this problem: he runs the application, selects “Original Workbook then just nothing happens. When he selects “Choose Save…” then this message appears:
Exception EFOpenError in module “filename”.dll at 009C477”
Why a dll link?
How solve it?


Looks like a compatibility problem. Which versions of Excel and Windows are used?


He has Excel for office 365 MSO (16.0.10730.20264) 32 bit. Windows 10 pro ves.1809 OS build 17763. 437. No antivirus installed.
I have generated the exe with xlspadlock 2018. Last days I have downloaded the 2019 version and sent him the new exe, but I have no feedback from him yet, if it works.