Thank you all! It only needed to be unblocked.

>It's related to Windows security zones. Most likely you have the help file on a network share and you need to unblock it.
>
>This can happen in a few different ways:
>
>* CHM files on a network share (in intranet security zone)
>* CHM file copied from a Web download or downloaded zip file
>
>This basically sets a file security attribute that then refuses to open the Web browser required to load the topic.
>
>Here's an old blog post that talks about some of the issues:
>
>Problems-with-opening-CHM-Help-files-from-Network-or-Internet
>
>>Hello all,
>>
>>I can launch the FoxPro help by pressing F1 but if I double click on a topic for example. I cannot see all the informations that should be displayed.
>>
>>Suggestions to correct this?