CHM file open blank Content-free solution

CHM file open blank without content shows the following

This is a very formal text, and there is no damage to the download. Close this file first.

We right-click on this file and select Properties to view

In the general we can see that this document is prompted from another computer and may be blocked to help protect the computer.

We trust this document, click Unlock, and if you don't feel safe, give it up. After the solution is shown as follows

Then we reopen the document test to open it normally, but also the contents of the normal display inside.

If you press this method or not open, to exclude whether the file has been damaged or banned by anti-virus software and other factors, I wish you good luck.