this happened on a new 2003server with R2. after installing rpro, tried to launch it,. as expected, it says that files need to be created. upon trying to create them it gets stuck in a loop of trying to create files, and saying that files need to be created.
to resolve right click on MY COMPUTER, go to PROPERTIES. once in SYSTEM PROPERTIES, go to ADVANCED tab, then under PERFORMANCE click on SETTINGS. Click on th DATA EXECUTION PREVENTION tab, and there are two settings. the correct setting is TURN ON DEP FOR ESSENTIAL WINDOWS PROGRAMS AND SERVICES. this used to be the windows default, but now the default is TURN ON DEP FOR ALL PROGRAMS AND SERVICES EXCEPT THOSE I SELECT.
after changing this setting, all was well.