• The MassMessage window is meant to serve as an internal news channel for all Revit users inside your company or group of users.
• The window is displayed when Revit starts.
• Change the URL to your custom HTML file using customToolsSettings.
• You can use it for sharing new families, templates, scripts, learning content etc. with your team.
• Older messages are stored in the Mass Messages archive. MassMessage can also be accessed via the CustomTools >>> About >>> Mass message command.

An example of MassMessage window usage

Default CustomTools Mass Message