The first consideration is where the help is going to be
installed.
If it is on the users PC, then you should use your existing
CHM format. You can use webhelp if you have RH6 or later and apply
the Mark of the Web. Note however that links to PDF files will not
work if you use that method.
It the help is on a server, then you should use webhelp. If
you use a CHM file, then it will not work without a registry change
which you should not make without the knowledge to the system
administrator.
If your existing help were in CHM format, you would know that
so I am guessing your help is installed locally. That brings us to
the next consideration, apart from the PDF issue. A CHM is a single
file. Webhelp is not compiled so you get a whole bunch of files and
folders. Your developers may not like that unless you can persuade
them the appearance outweighs that issue.
There is one more important consideration. Your developers
will have to change the calls to the help. Make sure they are
willing to do that.
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