About Custom Actions
Although standard actions are sufficient to execute an installation in most cases, custom actions enable the author of an installation package to extend the capabilities of standard actions by including executables, dynamic-link libraries, and script. Custom actions cannot be used in the sequence tables used for advertisement, the AdvtUISequence table and the AdvtExecuteSequence table.
The following sections provide more information about custom actions.
Synchronous and Asynchronous Custom Actions
Deferred Execution Custom Actions