Office Application Automation
Automating one application from another is often referred to as running code from a host application to automate another application. Although automating one Office application from another is generally accomplished in the same way, there are some important differences regarding how you work with each application.
When Microsoft® Visual Basic® for Applications (VBA) code references an object that is not installed, the Windows installer technology will attempt to install the required feature. In all Microsoft® Office applications except Microsoft® Outlook® and Microsoft® FrontPage®, you can use the FeatureInstall property to control what happens when an uninstalled object is referenced. When this property is set to the default (msoFeatureInstallOnDemand), any attempt to use an uninstalled object causes the Microsoft® Windows® installer to try to install the requested feature.
In some circumstances, this might take some time, and the user might believe that the machine has stopped responding to additional commands. To address this, you can set the FeatureInstall property to msoFeatureInstallOnDemandWithUI to display a progress meter so that users can see that something is happening as the feature is being installed.
If you want to trap the error that is returned and display your own dialog box to the user or take some other custom action, you can set the FeatureInstall property to msoFeatureInstallNone. For more information and details about application-specific behavior, search the Office application's Help index for "FeatureInstall property."
Office Objects and Object Models | Integrated Office Solution Development | Objects, Collections, and Object Models: Technology Backgrounder | Setting References | Object Variable Declaration | Automating the Visual Basic Editor | The Set Statement and the New Keyword in Automation | Single-Use vs. Multi-Use Applications | Using the CreateObject and GetObject Functions