Welcome to the forum.
It is possible to reverse engineer from a webhelp output or a
CHM output. I don't know about FlashHelp but I can point you to a
site with information about the webhelp procedure so that you can
see if that will work.
Click
here.
I notice you say you did not backup in time. I wonder if that
means you have backups and have just lost your work since a certain
point? If so, you could restore that and then use Rick's method to
recover just the lost changes, assuming the method does work for
FlashHelp.
Rick is US based so he will not be online until later to
comment on this. I'm guessing you are not US based, either that or
you are working in the early hours resolving this.
🙂
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