Hi,
Here is my practical experience,
I was also trying to change the password for an user using the following
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$ /sbin/passwd
Changing password for niraj
Invalid login name.
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Then I tried
=============================
$ /usr/bin/passwd niraj
Changing password for niraj
Old NIS password:
New password:
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ANd it worked !!!! ::)
After this I tried
$ which passwd
/sbin/passwd
I change my search path and it is working fine. you can also try with /usr/bin/passwd
-Niraj
Niraj.Verma@philips.com