Samba permission problem

[Shlomo Solomon]

I have a partition on my computer defined as a share on Samba. A user
on another machine can read and create files. Files are created as
rw-r--r-- as intended. But even though the user can create a file, the
new file can't be saved after editing/changing it.

I've looked at all the Samba parameters I could think of but can't find
anything. 

BTW - I always thought that "w" allows creating and also updating
existing files. What am I missing here?

-- 
Shlomo Solomon
http://the-solomons.net
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