I just looked at the thread
Rebuildm.exe needs the original master, pubs, msdb, and northwind files (both data and log). Rebuildm.exe copies these files into the installation directory of SQL Server 2000. When the copy completes, rebuildm.exe leaves all those files with the Read-only attribute set to on, which then prevents SQL Server from starting.
I not actually re built master from the rebuildm.exe command.
When it says needs the original files. From an administrative point of few - when first installing SQL is it best to keep the original copies somewhere in a RESTORE folder for this.
Or does the rebuildm.exe actually create new copies of this.