If you open a document that contains a digitally signed macro, you are prompted to select whether to trust the source if the following conditions are true:

• The digital certificate has not previously been trusted.
  
  -and-
  
  
• The security for your program is set to High or Medium.

You have the option to trust all currently installed add-ins and templates on your computer so that all files that are installed with Microsoft Office or added to the Office templates folder are trusted even though the files are not signed. This article describes how to specify the trusted sources for Digital Certificates.

Specifying Trusted Sources

Using trusted sources is a means of cataloging and allowing signed executables to run on a computer. By enabling this feature, you can select whether to allow executable code or programs to run from sources that can be identified or trusted.

An Administrator can select to turn off the trusted sources feature or to enable a list of trusted sources as a default. If this feature is selected, any future installable code (such as, add-ins, applets, executables, and so on) is automatically copied to, or run from, the user's computer.

To specify trusted sources in Word, Excel, or PowerPoint, follow these steps:

1. On the Tools menu, point to Macro, and then click Security.
2. Click the Trusted Sources tab.
3. To trust all add-ins and templates currently installed on the computer, select the Trust all installed add-ins and templates check box.

You can add trusted sources by accepting the request to trust an applet or program the first time it tries to run. Macro security must be set at Medium or High to force this request.

NOTE: The Security dialog box is available from Word, PowerPoint, and Excel. It is not available in Access.