Configuring the Trust Center

The Trust Center is a separate dialog box from the main PowerPoint options; it contains categories for controlling the permissions that users, programs, and Internet sites have to access your computer through PowerPoint. After clicking the Trust Center category in the PowerPoint Options dialog box, you can click the Trust Center Settings button to access it.

Setting Up Trusted Locations

A trusted location is a location that you verify to be threat-free. When a presentation file is stored in a trusted location, PowerPoint allows macros to run without the usual safeguards (discussed later in this Appendix). To allow free access to your macros in a presentation file, you should store it in a trusted location.

The following folders are trusted by default:

• Program Files\Microsoft Office\Document Themes 12

• Program Files\Microsoft Office\Templates

• Users\ username \Application Data\Microsoft\Addins

• Users\ username \Application Data\Microsoft\Templates

You can also add more trusted locations. For example, you may want to trust a folder in which you store your presentation files for a certain client.

To add a trusted location, follow these steps:

1. Choose Office PowerPoint Options.

2. Click Trust Center, and click the Trust Center Settings button.

3. Click Trusted Locations. A list of currently trusted locations appears, as shown in Figure B.2.

4. Click Add New Location.

5. Click the Browse button, browse to the location you want, and then click OK.

6. (Optional) If you want, you can select the Subfolders of This Location Are Also Trusted check box.

7. Click OK.

Figure B.2 shows other settings and buttons that you can also select:

• Allow trusted locations on my network: Enables you to add trusted locations that exist other than on your local computer.

• Disable all Trusted Locations, only files signed by Trusted Publishers will be trusted: This setting does just what its name says. You will learn more about trusted publishers later in this Appendix.

• Remove: Removes a trusted location from the list. (There is no confirmation; it is removed immediately.)

• Modify: Opens the Trusted Location dialog box for a location, so that you can change its path or options.

Figure B.2: You can set up new trusted locations in the Trust Center dialog box.

Working with Trusted Publishers

Another way to trust a macro is to verify that it comes from a trusted publisher. The Macro Settings (covered in the next section) enable you to specify what should happen when a macro from a trusted publisher wants to run outside of a trusted location.

When you open a presentation that includes one or more signed macros, PowerPoint prompts you, asking whether or not you want to trust macros from that signer. Information about the signer's certificate appears, including the name, the issuing authority, and the valid dates. If you choose Yes, then this signer is added to your Trusted Publishers list. If you have not yet added a signer to the Trusted Publishers list, then the list will be blank in the Trust Center dialog box.

If you have a trusted publisher on your list, you can select it and then click View to view its information, or click Remove to remove it from the Trusted Publishers list.

Macro Settings

Macro settings apply only to macros that are stored in presentations that are not in trusted locations. These settings determine whether or not the macro should run, and whether you should receive notification, as shown in Figure B.3.

Figure B.3: You can specify what should happen when a presentation outside a trusted location tries to run a macro.

ActiveX Settings

ActiveX controls are somewhat like macros in that they contain code to be executed. Programmers write them to extend the capabilities of an application. These controls have their own set of behaviors that you can configure when they run from outside a trusted location, as shown in Figure B.4.

Figure B.4: You can specify what should happen when a presentation outside a trusted location tries to run an ActiveX control.

Add-Ins

An add-in is like a super macro. Add-ins can often dramatically extend the capabilities of an application, by adding new tabs on the Ribbon, new buttons, and more. Because they connect with the application at a fairly low level, they can be devastating if they contain viruses. (It is not common for add-is to contain viruses, but you never know what could happen.) You can specify that addins must be signed by a trusted publisher, or you can disable all add-ins from running.

Message Bar

By default, when content is blocked, a message bar appears between the Ribbon and the presentation to let you know what has happened. You can enable or disable the appearance of this message bar.

Privacy Options

It is usually safe to connect to the Internet to download content such as clip art and templates, and to send feedback to Microsoft about errors and usage. However, some people are concerned about security, and prefer to control their computer's connection to outside sources such as the Internet. (Yes, I know, just because you are paranoid does not mean that someone is not out to get you.) In the Privacy Options category, you can find a set of check boxes where you can decide what connectivity to allow.