How to time out?

[Pranay]

Hi,

    I configured Samba on my FreeBSD machine & I can browse my machine
through Windows happily. But one problem I'm facing when I log in first
time it asked me for a user name & password. I gave it. Authentication
was successful. When I close that particular window & again try to
connect it...it doesn't ask me for the user name & password, directly my
shares r get opened.
    Is there any option to set time out or anything else from which it
can ask Usernmae & password everytime while browsing that machine...???

Thanx & Regatds,

Pranay