Start stage

The Start stage properties dialog allows you to assign parameters to a Start stage.

Start stage location

If the Start stage is on the Main Page of the process, then the start parameters are required each time the process is started either from Control Room or via another process. These parameters are commonly referred to as ‘start-up parameters’.

The collection data type cannot be used as a start-up parameter if the process is to be started from Control Room. However, in Blue Prism Desktop processes, the collection data type can be used to pass data to sub-pages.To learn more about setting start-up parameters in Control Room, see Start Parameters.

If the Start stage is on a sub-page within the process, then the start parameters must be passed whenever that page is called in the process. This is done using a Page reference stage.

Blue Prism Desktop processes

If you are developing a process for use in Blue Prism Desktop, a Start stage can be used to add start-up parameters. When input parameters are added to a Start stage, they are displayed as a form in Blue Prism Desktop This enables the Desktop client user to enter the required parameters before running the process.

If your process includes start-up parameters, a debug form displays the input fields when run in Process Studio in debug mode. This enables you to create and test a process without having to publish and run it in Blue Prism Desktop.

The style of the debug form displayed in Process Studio does not match the style used in the Desktop user interface, but provides an accurate representation of the content.

The following image shows a Start stage as it appears in Control Room, and the same Start stage in Blue Prism Desktop:

Start stage input properties

Input property



Enter a name for the Start stage. This will be displayed on the process diagram.

Input Name

Enter a name for the input parameter.

When running in Blue Prism Desktop, this is displayed as the field title on the form.


Enter a description for the input parameter, if required.

When running in Blue Prism Desktop, this displays below the input name on the form and can be used to add help text for the input.

Data Type

Select a data type for the input parameter. The following data types are supported:

  • Collection
  • Fields with a data type of collection will not display in forms in Desktop, or debug forms in Process Studio for main processes, but can be used to pass data to sub-pages.

  • Date
  • DateTime
  • Flag
  • Number
  • Password
  • Text
  • Time
  • TimeSpan
  • Image
  • Binary

The display of default values for Image and Binary data types is not currently supported in Blue Prism Desktop.

Store In

Specify the data item or collection in which the input value can be stored.