The Set Build Status Message action allows you to add a custom message to the build Status screen. This message can be anything you like - so for example it could be "Running Installer" or "Uploading". It's a message that will give you an indication as to what the current progress of the build is.
The above screen shot shows the custom status message "Scanning for files".
Details
Status Message
The message you want to appear below the progress bar. Variable references are expanded, eg. "We're now running project %CurrentProject%".
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