matt
for a question like that it would be really helpful to post your computer/operating system specs: the files that you're after are saved differently on each platform and for each archiCAD version . . .
also, you should be aware that preference files are among the first to become corrupt (at least on a mac!), so you should be careful when backing them up for future use to ensure they are 'clean'. . .
~/archiben
b e n f r o s t
b f [a t ] p l a n b a r c h i t e c t u r e [d o t] n z
archicad | sketchup! | coffeecup