Microsoft Office Tutorials and References
In Depth Information
• Add a Digital Signature. Think of the number of business and legal documents
that require a signature: checks, wills, sales contracts, leases, credit card
receipts…. You sign a document to show that you approve it or agree to its terms.
A forged signature makes the document invalid, so some documents require a
witness to confirm that you’re the one who signed it.
When you email or share some documents, you want to be able to prove they
come from you. But you can’t whip out a pen and dash off your signature on
an email. That’s where digital signatures come in. A digital signature is an
electronic tag that verifies a document’s authenticity—it proves that the document
comes from you and that nobody has tampered with it since it left your desk.
To put your electronic John Hancock on a document, choose Add a Digital
Signature from the Protect Document menu. A dialog box opens, offering two
ways to add a digital signature to your document:
— Get a digital ID from a Microsoft partner. A third-party digital signature
is like getting someone to witness your signature—it guarantees that you’re
the one who signed the document. If you choose this option, your web
browser opens and takes you to the Office Marketplace, where you can
choose a digital ID provider, such as GlobalSign.
— Create your own digital ID. When you choose this option, it’s like signing
a check or a credit card slip without anyone standing by to verify that you’re
you; it’s less secure than third-party verification, but it shows to your own
satisfaction that the document is yours and not altered by anyone since you
The first time you select this option and click OK, Word opens a dialog
box where you can set up your digital signature: name (required), email
address, organization, and location (optional). Type in your signature
information and click Create. Now you’ve got a digital signature to attach to
Next time you opt to create your own digital ID, Word opens the Sign
dialog box, shown in Figure 9-11. Type in a brief description of your purpose
for signing the document, and then click Sign. Word makes your
document read-only (to prevent any changes); attaches your digital signature;
and adds a Signatures button, which looks like a document seal, to the
Note: You can also attach digital signatures to Excel workbooks and PowerPoint presentations.