Page 190 - Excel Data Analysis

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EXCEL DATA ANALYSIS

SET MACRO SECURITY (CONTINUED)

f you create a data analysis workbook containing macros assigned the signature, but they do not certify it like the
that you want to distribute to others, you should ones you acquire from a commercial agency.
I consider assigning a digital signature to the workbook. After you acquire a digital signature, you need to attach it to
As previously discussed, a digital signature provides you your macros. Attaching a digital signature is similar to
assurance that the workbook file is valid and has not been sealing an envelope: If an envelope arrives sealed, no one
altered by other sources.
has tampered with its contents. Keep in mind that the
You can assign a digital signature to any of your macros. You digital signature stays attached to the macro only until
attach signatures to code in a macro, or file, to signify that someone modifies it. Excel even removes the digital
the code is valid and that no one has modified it since you signature if you modify the VBA code. Therefore, if you
applied the signature. make any modifications at all to the macro code, you need
to re-attach the digital signature.
No matter what type of digital signature you choose to
assign to your macro, a certified digital signature or If you are not sure whether you have modified a macro
personal digital signature, you follow the same steps. You since attaching the digital signature, you can check if the
must acquire the digital signature before you can assign it to signature is attached in the Digital Signature dialog box. If a
the macro. Personal digital signatures work well for digital signature is attached, the name of the signature
indicating that no one has altered the macro since you displays in the Certificate Name field in the dialog box.
SET MACRO SECURITY (CONTINUED)

Module1

ASSIGN A DIGITAL SIGNATURE ■ The macro code is ■ The Digital Signature ‹ Click Choose.
TO A MACRO
displayed in the Code dialog box opens and
⁄ Select the module that window. indicates whether a digital
contains the macro you want ¤ Click Tools ➪ Digital signature certificate is
to sign. currently assigned to the
Signature.
selected macro.

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