I have a Linux server running SAMBA to share data with other Windows hosts. My conf file are:
smb.conf
[global]
workgroup = WORKGROUP
encrypt passwords = yes
smb passwd file = /etc/samba/smbpasswd
username map = /etc/samba/smbusers
security = user

log file = /etc/samba/log/%m.log

[TEST_SB]
comment = For testing only
path = /usr/test
read only = no
valid users = devuser

[PUBLIC_DATA]
comment = Public data
path = /home/sharedata
read only = no
valid users = devuser


smbusers:
root = administrator admin
devuser = devusers share
nobody = guest pcguest smbguest

The problem is:
When I using windows to browse, it displays 2 folder ok. But when I try to access it, error happen:
-With /home/sharedata: Folder does not exist error
-With /usr/test: it browse the content of the folder ok, but just read only

NOTE:
-In Linux machine, both folders can be read and written by any user(777)
-Firewall is disable
-I've add samba user devuser and it's samba password also
-/, /boot, /usr are 3 primary partitions, /home anh /swap are 2 extended ones.

Can any body help me. Thanks in advance.

does windows ask you to enter a user/password when you browse to the samba server?

Yes, and after typing the correct username&password, we will see the 2 shared folder, seems very normal.

do you have a corresponding linux account for your smb account?
you need to create a devuser linux account, then type:
smbpassword -a devuser
reenter the password twice

Ofcourse yes, I have a Linux account devuser previous. So headache!!!

Oops, I finally found the way to solve this problem. The reason is SELinux. I just disabled it and everything was ok.
Thanks Finlay for your attendtion.