If you are the originator of a document, the first signature applied to secure the document can be a certifying signature. Before certifying a document, make sure all modifications and changes are made to the file, as making changes after certification can corrupt the signature.

Follow these steps to certify a document using a custom appearance:

1. Choose File > Save as Certified Document to open an information dialog box, explaining that certification vouches for the contents of the document and that you need a digital ID to proceed. Click OK to close the information dialog box.

   Note	If you intend to use a third-party certification system, click Get Digital ID From Adobe Partner, and proceed through the prompts.

2. The Save as Certified Document Choose Allowable Actions dialog box opens. Choose an option from the Allowable Actions drop-down list. The options include commenting and form fill-in actions, no changes, or only allow form fill-in actions (Figure 10.8).

3. To prevent anyone from trying to remove the signature, click the Lock the Certifying signature so that it can't be cleared or deleted by anyone checkbox.

4. Click Next; the Save as Certified Document Warnings dialog box opens. A list of items that can jeopardize the integrity of the certification are listed. In the example shown in Figure 10.9, the document contains active URLs as well as allowing commenting on the document. A default warning is selected on the dialog, which explains that the content is used to enhance the...