Encryption

Hello All:

I am working on an Excel workbook with VBA that will be used to print
temporary checks for our customers. I have everything working great, but I
want to be able to save the customer information each time a new customer is
entered for future reference. To do this, I would need to save names,
addresses, and account numbers somewhere, but of course security is my first
issue. How should I go about doing this?

I have worked with a couple of encryption modules, but they encrypt a string
to (what I assume is) an array of bytes that I can't get into a cell (well,
I can but it shows up as Chinese). What I really need is something that
will encrypt a string to another string, but 1, are there any modules that
do that, and 2, is that secure enough? How can I save these byte values
somewhere that I can get them back? Any help would be greatly appreciated.

Lydon D. Bergin
MCP, MOS

Unfortunately I'm not one that really has an answer for you, but when you
talk about the encryption to a cell and it looks like chinese, well it seems
that the encryption worked. You would just need some way to decrypt it as
needed.

Depending on your actual requirement to encrypt/hide the data, if you store
the data on a worksheet that is Very Hidden (not just hidden) and lock your
code so that the list of sheets can not be seen, it's not readily visible,
but may not meet your requirements.

"Lydon Bergin" wrote:

> Hello All:
>
> I am working on an Excel workbook with VBA that will be used to print
> temporary checks for our customers. I have everything working great, but I
> want to be able to save the customer information each time a new customer is
> entered for future reference. To do this, I would need to save names,
> addresses, and account numbers somewhere, but of course security is my first
> issue. How should I go about doing this?
>
> I have worked with a couple of encryption modules, but they encrypt a string
> to (what I assume is) an array of bytes that I can't get into a cell (well,
> I can but it shows up as Chinese). What I really need is something that
> will encrypt a string to another string, but 1, are there any modules that
> do that, and 2, is that secure enough? How can I save these byte values
> somewhere that I can get them back? Any help would be greatly appreciated.
>
> Lydon D. Bergin
> MCP, MOS
>
>
>

This link may be of some value to you.

http://www.mcgimpsey.com/excel/fileandvbapwords.html

It does not directly answer your question but it give you some good general
insight into protection.
--
HTH...

Jim Thomlinson


"Lydon Bergin" wrote:

> Hello All:
>
> I am working on an Excel workbook with VBA that will be used to print
> temporary checks for our customers. I have everything working great, but I
> want to be able to save the customer information each time a new customer is
> entered for future reference. To do this, I would need to save names,
> addresses, and account numbers somewhere, but of course security is my first
> issue. How should I go about doing this?
>
> I have worked with a couple of encryption modules, but they encrypt a string
> to (what I assume is) an array of bytes that I can't get into a cell (well,
> I can but it shows up as Chinese). What I really need is something that
> will encrypt a string to another string, but 1, are there any modules that
> do that, and 2, is that secure enough? How can I save these byte values
> somewhere that I can get them back? Any help would be greatly appreciated.
>
> Lydon D. Bergin
> MCP, MOS
>
>
>

You should not rely on Excel security when storing "sensitive" information.
Workbook/worksheet/VBA project passwords are all easily cracked by anyone
who knows enough to google for the method.

If your encryption/decryption method is implemented in VBA then it would
also be accessible to anyone who obtained your file, and they could use your
routine to decrypt the data.

Tim



--
Tim Williams
Palo Alto, CA


"Lydon Bergin" <[email protected]> wrote in message
news:%[email protected]...
> Hello All:
>
> I am working on an Excel workbook with VBA that will be used to print
> temporary checks for our customers. I have everything working great, but
I
> want to be able to save the customer information each time a new customer
is
> entered for future reference. To do this, I would need to save names,
> addresses, and account numbers somewhere, but of course security is my
first
> issue. How should I go about doing this?
>
> I have worked with a couple of encryption modules, but they encrypt a
string
> to (what I assume is) an array of bytes that I can't get into a cell
(well,
> I can but it shows up as Chinese). What I really need is something that
> will encrypt a string to another string, but 1, are there any modules that
> do that, and 2, is that secure enough? How can I save these byte values
> somewhere that I can get them back? Any help would be greatly
appreciated.
>
> Lydon D. Bergin
> MCP, MOS
>
>

>"Tim Williams" <timjwilliams at gmail dot com> wrote in message
> >news:[email protected]...
> You should not rely on Excel security when storing "sensitive"
> information.
> Workbook/worksheet/VBA project passwords are all easily cracked by anyone
> who knows enough to google for the method.
>
> If your encryption/decryption method is implemented in VBA then it would
> also be accessible to anyone who obtained your file, and they could use
> your
> routine to decrypt the data.
>
> Tim

Any idea how (besides saving to a database) I can save this information
securely?

Lydon D. Bergin
MCP, MOS

The problem is denying access to those for which access is not intended.

Encryption might be one form of solution, but it doesn't appear one very
useful if you are going to use the data on a daily basis.

If you can control physical/electronic access to the file, that should be
sufficient - really depends on what the threat is.

--
Regards,
Tom Ogilvy

"Lydon Bergin" <[email protected]> wrote in message
news:%[email protected]...
> >"Tim Williams" <timjwilliams at gmail dot com> wrote in message
> > >news:[email protected]...
> > You should not rely on Excel security when storing "sensitive"
> > information.
> > Workbook/worksheet/VBA project passwords are all easily cracked by
anyone
> > who knows enough to google for the method.
> >
> > If your encryption/decryption method is implemented in VBA then it would
> > also be accessible to anyone who obtained your file, and they could use
> > your
> > routine to decrypt the data.
> >
> > Tim
>
> Any idea how (besides saving to a database) I can save this information
> securely?
>
> Lydon D. Bergin
> MCP, MOS
>
>

If you can find a suitable encryption/decryption algorithm which uses a
passphrase not stored in the workbook (you would have to enter it manually
in each session) then that might work.

It really depends on how secure you need the information to be. As Tom
notes, just controlling access to the file might be enough for your
situation.

Tim.

--
Tim Williams
Palo Alto, CA


"Lydon Bergin" <[email protected]> wrote in message
news:%[email protected]...
> >"Tim Williams" <timjwilliams at gmail dot com> wrote in message
> > >news:[email protected]...
> > You should not rely on Excel security when storing "sensitive"
> > information.
> > Workbook/worksheet/VBA project passwords are all easily cracked by
anyone
> > who knows enough to google for the method.
> >
> > If your encryption/decryption method is implemented in VBA then it would
> > also be accessible to anyone who obtained your file, and they could use
> > your
> > routine to decrypt the data.
> >
> > Tim
>
> Any idea how (besides saving to a database) I can save this information
> securely?
>
> Lydon D. Bergin
> MCP, MOS
>
>