There are different extensions that I should backup.
It's a Win2k Server SP4 with 5.5 GB data on C:\, and about 120 GB on D:\. (nsf databases)
Backupexec copies only 2.6 GB from C:\ and only 1 GB from D:\. without any error message. no open file problems, no credential problems, no nothing.
With the same backup job from a remote server it runs correctly, all the 125.5 GB data from the two drives copied successfully.