I have vsftpd running on my RHEL4 system. The problem is when I do a FTP session from WinXP, it does not ask for a username/password.

I have used system-conf-users to add the two users/passwords that are to be used. I also need to only allow each of the two users to have their own ftp folder. So what are the steps to this? I am still a newby to linux but starting to understand linuxese. LOL

You might have anonymous enabled. Check your /etc/vsftpd.conf configuration for additional settings you have in place.

anonymous_enabled=NO.

Guess I should clarify....when I do a ftp session on the linux box it does ask for a username/password. On my WinXP system when I do a ftp://10.150.xxx.xxx, I get a ftp session but no prompt for username/password. it puts me in the PUB folder.

Somehow that sounds like you still have anonymous ftp enabled. Can you post your full vsftpd.conf file?

Where are you doing the FTP on your XP system? In Internet Explorer? Another browser?

To allow only the 2 specific users, you can use the vsftpd.allow and/or vsftpd.deny files. Easiest is to put only
the 2 usernames into vsftpd.allow. You may need to check your vsftpd config to see if the .allow and .deny files are used
and correctly set up.

You may also want to use virtual users rather than real local ones. The chroot option to lock both users into a given directory (ie their home directory) can be useful in this case too.
If both users need specific settings, use the per-user-config option.