Samba. Cannot delete files on network share

Its Samba share on my router-attached NTFS partition.
Keep deny my permission........
Through winscp, this  /opt/etc/smb.conf

"Browseable = yes
Writable = yes
read only = no"

chmod a -R option to make it recursively change permissions on all files/sub-directories.
chmod -R 777 ./data-folder/*
Changing the permissions of the directory is not what you need to do. You need to change the permissions of the SHARE. Think of the share as a layer inbetween the directory and the remote user. The user sees the permissions of the SHARE not the directory. The share only has access to the folder as far as the directory permissions let it.

So if the directory is rwx, the share can do whatever it wants. If the directory is r-x, then the share can at best be r-x, but it can aslo be r-- or --x or ---, but it can never be rwx or -w-, or anything with a write.

These two statements are not so. The Samba server in no way grants or denies permissions for the file system. Samba only authenticates the users access to the share. All authorization is done through the FS permissions. File creation can be controlled Samba with create and dir masks. In my Samba setup I force a common group (smbusers) even if it is a guest (I named smbguest). It's even possible to limit the authenticated users ability to delete files, but this is done using the Linux "sticky bit", not Samba. 

Samba can control the permissions of the share. The path to a Samba share can have a mode of 777 (rwxrwxrwx) but the share definition can limit the share to be read only.

It's just like in Windows if you disable "Simple file sharing" then for each folder you see a Share tab and a Security tab. The Security tab controls the permissions of the folder on the local system while the Share tab controls the effective permissions of a remote user. The Share permissions can be as lenient but no more lenient then the permissions set by the Security tab.

The same goes for Samba. The directory permissions are just the limiting factor. If the OP wants to control the share permissions through the filesystem permissions, then he should enable full read-write access through the share and adjust the filesystem accordingly. What seems to be the case though, is that the default permissions for the Samba share are read-only.

still with smb.conf. You need to change the fmask and dmask of the files that are created. You should want something like read-write for files and read-write-execute for folders. (6 and 7 respectively) Keep in mind that when talking about file permissions, "mask" is the opposite of what you want to take place (so 1 and 0 respectively)

quote the smb.conf man page, "The access rights granted by the server are masked by the access rights granted to the specified or guest UNIX user by the host system. The server does not grant more access than the host system grants."

Through webgio restarted samba daemons after changing the file settings.