Well thanks to all who replied re my status 13 problem. I messed around 
for ages uninstalling client s/w etc checking in all the logs which 
didnt seem to help to be honest.

someone had replied mentioning a netbios name of the client begin set in 
the policies, so i went down looking at client name and changed the 
client name on the backup server to the real name of the client as 
previously i had been putting an _machine_function  on the end in 
netbackup and the master server hosts file to make the machines 
understandable instead of just weird numbers and letters which they are 
named in this project.

Anyway i changed the client s/w to have the correct name and changed the 
policies and host file to have the real machine name and low and behold 
backups have worked.!!

Its very very odd why, as nothing seemed to mention this in the logs and 
the status 13 comes up almost immediately when you started the backups 
after tape mount. The very odd thing is other windows 2000 clients i am 
backing up  have had their names different from the the actual windows 
machine name and they have been working, so im not sure why these 2 
clients failed.

Thanks anyway and 1 to blog

Dave