I'm developing a spreadsheet for an end user to interact with via user forms.
I want to hide and protect the code behind the application. The user, via
user forms, goes to a financial web site and downloads data into Quicken.
Next he produces reports in Quicken and copies them to the clipboard for
pasting into Excel spreadsheets. What would be the best (recommended?) way to
protect the VBA code and formulas? I've considered two approaches: One,
creating an add-in, or two, write all the code in a separate workbook which
the user's workbook calls and then hides when his workbook opens. Can someone
who does a lot of this kind of thing recommend one approach over the other,
or suggest a completely different and/or better strategy. All suggestions
will be greatly appreciated.

I would use an addin.

What kind of addin depends on the degree of security you need.
a VBA XLA addin is fairly easily cracked
a .net automation addin is harder to crack but is slightly more complex to
develop and install
a VB6 automation addin is extremely difficult to crack, but a VB6 compiler
is hard to find
an XLL addin written in C will also be extremely difficult to crack, but
considerably harder to write


Charles
___________________________________
The Excel Calculation Site
http://www.decisionmodels.com

"JCIrish" wrote in message
...
I'm developing a spreadsheet for an end user to interact with via user
forms.
I want to hide and protect the code behind the application. The user, via
user forms, goes to a financial web site and downloads data into Quicken.
Next he produces reports in Quicken and copies them to the clipboard for
pasting into Excel spreadsheets. What would be the best (recommended?) way
to
protect the VBA code and formulas? I've considered two approaches: One,
creating an add-in, or two, write all the code in a separate workbook
which
the user's workbook calls and then hides when his workbook opens. Can
someone
who does a lot of this kind of thing recommend one approach over the
other,
or suggest a completely different and/or better strategy. All suggestions
will be greatly appreciated.

Thanks, Charles, for the very useful reply. You've answered my question.

"Charles Williams" wrote:

I would use an addin.

What kind of addin depends on the degree of security you need.
a VBA XLA addin is fairly easily cracked
a .net automation addin is harder to crack but is slightly more complex to
develop and install
a VB6 automation addin is extremely difficult to crack, but a VB6 compiler
is hard to find
an XLL addin written in C will also be extremely difficult to crack, but
considerably harder to write


Charles
___________________________________
The Excel Calculation Site
http://www.decisionmodels.com

"JCIrish" wrote in message
...
I'm developing a spreadsheet for an end user to interact with via user
forms.
I want to hide and protect the code behind the application. The user, via
user forms, goes to a financial web site and downloads data into Quicken.
Next he produces reports in Quicken and copies them to the clipboard for
pasting into Excel spreadsheets. What would be the best (recommended?) way
to
protect the VBA code and formulas? I've considered two approaches: One,
creating an add-in, or two, write all the code in a separate workbook
which
the user's workbook calls and then hides when his workbook opens. Can
someone
who does a lot of this kind of thing recommend one approach over the
other,
or suggest a completely different and/or better strategy. All suggestions
will be greatly appreciated.