problem with the documentation file

having problem with chm file. i dont know what im doing before. Can somebody give suggestion?

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Some one reported a similar problem in forum before. It was chm file was disabled in the system.

Try right click the chm file and see what you can do with it.

In earlier versions of Nvil I had to always right click on the chm file > go to properties > and check unblock for it to work in Nvil.

I haven't had this issue in recent versions (past 4 months or so).

Right Click and unblock is the solution. Thanks kevjon  and Istonia!