Failed to generate HTML5 Output 2019

[#1]

I'm trying to generate an HTML5 output and get this error (Robohelp 2019). Anyone know why this might be? I already tried closing the project and opening it back up. 

[#2]

Right-click on the output preset and check the log. It might provide more information, or at least clues about how far the process got.

[#3]

Are you all patched up? Check Help > Updates to check.