(NB This question is similar to http://www.experts-exchange.com/OS/Microsoft_Operating_Systems/Server/2003_Server/Q_24587908.html
but the page linked to in the accepted answer is missing now, presumed defunct...)
I have an SBS 2003 server but space was filling up quickly on the system partition (C:\) and less than 1GB left.
I tracked down 9GB of data to the following folder:
C:\Documents and Settings\All Users\Application Data\Microsoft\Windows NT\NTBackup\catalogs51
which contains files ending in extension .V01 (mainly, well 99% of them anyhow)...
dating way back in time to the initial installation of the server 7 years ago
having read up the other question and some of the answers I decided to delete all but those .V01 files from this year (and a .SM and a .VDD from the end of last year) which got rid of 8GB.
Just worried if my backup is now going to be screwed?
I don't mind if a restore takes a bit longer...