I haven't been able to find a clear answer to this question.
From the HTMLHelp API, we simply ask for the help file name - no
path - and the help engine finds the help file. A problem came up
when two colleagues were sharing data files across a network. Both
had our software and help installed on their computers. When one
user tried to open the help, they got an "action canceled" message
in the content pane. After some troubleshooting we found that
Windows was trying to access the other user's help file across the
network because it used the "current directory" first and found a
help file with the correct name.
From what I have read, it should always look in the program
directory first. So I'm baffled as how this happened and what to do
about it other than encouraging users not to save shared data in
their program directory. Any ideas?