You probably had an UNSUCCESSFUL attempt using the adduser command. The "vipw" may have incorrectly set the user password. In turn, it created two locked file called "ptmp" (password temp file), and "gtmp" (group temp file) in the /etc directory.
Removing the /etc/ptmp and /etc/gtmp locked files should take care of your problem.
Article Change History:
22 Aug 1994 - Added the reference to gtmp file.
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