Need some Expert help here. PLEASSSSEEEEEEE !!!

I have set up the above as mention in the subject. Everything is working perfectly and is still running normally with no error or whatsoever.

However, I realised at the root directory, "/". There are directories created like "no such user root", "no such user qscand", "no such user abdcd@abc.com" and many others. The directories are empty. Try to find the error in the log files in qmail, qscanmail etc but can't find anything wrong.

Everyday, I have to log in to delete these extra directories.

Can anyone help? As there are too many Qmail related programs installed I can't tell where is the problem.