Thanks Mark and Reeza.  I'm still not certain what the problem was as it was the same copy of XP as previously used.  I've worked around the problem by installing with the expired SID file and then updating the licence with the current SID file.  Many thank, Jim ... View more

Many thanks, Jim ... View more

Thanks very much! I'm (planning on!) performing a survival analysis - blood pressure control to time defined end point. I'll give the code a try now. Many thanks again, Jim ... View more