You may have noticed that that “welcome” email message lacks a certain freshness after awhile. Further, it is entirely devoid of any information that might help users find help on your local instance of SharePoint. How, then, to modify this rather stale bit of HTML?
I found the answer though our friends in the TechNet Social:
Who in turn got if from the venerable EggHead Cafe:
To summarize, modify the HTML code starting at line 5219 of the following RESX file in your “12” hive:
C:Program FilesCommon FilesMicrosoft Sharedweb serverextensions12Resourcescore.en-US.resx