Nitro PDF Professional User Guide

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Nitro PDF Professional User Guide
1. On the Secure and Sign tab, in the Digital IDs group, click My Digital IDs .
2. Click Trusted Contacts.
3. Highlight the contact to export, and then click Export.
4. In the Save As dialog, name the certificate and click Save.
To share public key certificates:
1. On the Secure and Sign tab, in the Digital IDs group, click My Digital IDs .
2. Highlight the contact to share with, click Request.
3. Enter your contact details.
4. Click the Include my certificate in email checkbox, and then select the certificate to share.
5. Click Next.
6. Enter the recipient’s email address, and then click Send.
7. Once the information and certificate are moved to your email client, click Send.
11. Digital signatures
A digital signature is like a paper-based signature – each giving you a method for adding a unique identifier
to a document. Both provide you with an easy way to show a person signed a particular document at a
particular time, but a digital signature goes further as it can ensure that the document content has not been
tampered with after it was signed. In addition, the document version history can let recipients see when a
document was signed and see when any changes were made to it. This revision history is encrypted and
stored inside the PDF and can be viewed at anytime via the Signatures pane.
To digitally sign a PDF document, you must have a digital ID, and to verify other people’s signatures, you
must first share your digital IDs and add each other to your Trusted Contacts list.
· Edit signature fields
· Insert blank signature field
· Customizing signature appearance
· Create a digital ID
· Add people to your Trusted Contacts
11.1 Using digital signatures
Each time a signature is applied to a document, a new message digest is created. This digest stores an
encrypted ‘hash’ version of the document (taken at the time of signing) and then embeds it along with the
signature inside the document. When a recipient receives the file and validates the signature, another digest
is generated and then compared with the original digest to confirm they have remained the same.
Tip: The embedded certificate verifies the signer’s identity, while the message digest verifies
the content has not changed.
To digitally sign a document:
1. On the Secure and Sign ribbon, in the Signatures group, click Sign .
2. One a page, click and drag to place where you would like the signature to appear.
3. In the Apply Digital Signature dialog, select the digital ID to use, and then click Next.
4. Select the reason for signing from the list, or type your own reason for signing.
5. Click the option to save the signed PDF as a new file or save it to the current document.
6. Click Finish.
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