The renderMessageManager Core Interface introduced in 3ds Max 2011 exposes the Render Message window to MAXScript.

Interface: renderMessageManager 

Properties:

renderMessageManager.OpenOnError : boolean : Read|Write      

Get/set whether to open the Render Message window when an error occurs in the renderer.

renderMessageManager.ShowInfoMessage : boolean : Read|Write   

Get/set whether to show info level messages in the Render Message window.

renderMessageManager.ShowProgressMessage : boolean : Read|Write 

Get/set whether to show progress level messages in the Render Message window.

renderMessageManager.LogDebugMessage : boolean : Read|Write 

Get/set whether to show debug level messages in the Render Message window.

renderMessageManager.LogFilename : string : Read|Write 

Get/set the name of the file to write the log to.

renderMessageManager.LogFileON : boolean : Read|Write 

Get/set whether to save the log to the log file or not.

renderMessageManager.LogFileAppend : boolean : Read|Write 

Get/set whether to append to the file specified by the .LogFilename property, or to overwrite any existing log file.

Methods:

<boolean>renderMessageManager.OpenWindow() 

Opens the Render Message window.

Returns true on success, false on failure.

<void>renderMessageManager.HideWindow() 

Hides the Render Message window.

<void>renderMessageManager.ClearWindow() 

Clears the Render Message window.

This does not affect the log file if logging to file is enabled.