Datasheet

Assign a Digital
Signature to a Macro
A
digital signature provides assurance that a
workbook file is valid and no one has altered it.
There are two types of digital signatures:
personal digital signatures and commercial digital
signatures. You can create a personal digital signature by
using the Microsoft Selfcert.exe tool, or you can purchase
a digital signature. Refer to the section, “Create a Digital
Signature,” to learn how to create digital signatures.
After you create a digital signature, you must attach it to
your workbook. Attaching a digital signature is similar to
sealing an envelope. If an envelope arrives sealed, you
have some level of assurance that no one has tampered
with its contents.
Use the Digital Signature dialog box to attach a digital
signature. The Visual Basic Editor is a separate Excel
module that you can use to edit your macro. You access
the Digital Signature dialog box by opening the Visual
Basic Editor. The Digital Signature dialog box lists valid
certificates. You can use the Digital Signature dialog box
to view certificates and to select the one you want to use.
Unless you have on your computer a valid digital
signature certificate for the signature used to sign a
macro, Excel removes the digital signature if you modify
a macro in a workbook, and you must reattach it. If you
are not sure if a workbook has a digital signature, you
can check the signature by reviewing the Digital
Signature dialog box. If a workbook has a digital
signature, the name of the signature appears in the
Certificate Name field. If you click the Remove button in
the Digital Signature dialog box, Excel removes the
digital signature.
1 Click the Developer tab.
Note:
See the section, “Introducing Macros,” to learn how to
display the Developer tab.
2 Click Visual Basic in the Code group.
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Assign a Digital Signature to a Macro
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The Visual Basic Editor appears.
3 Click Tools ➔ Digital Signature.
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