Re: BUG #1051: Cannot remove groups

"PostgreSQL Bugs List" <pgsql-bugs@postgresql.org> writes:
> I tried to install all from  fresh with:
> ...
> But that dind't affect the groups or users. This was verified by running
> select from pg_group and pg_users immedately after total recreation.

Your trace shows no sign of having stopped the postmaster before
re-initdb'ing or starting it again afterwards.  I think you've got some
unholy combination of old and new tables inside the postmaster.  It'd be
a good idea to try again with those steps included.  (I'm not sure just
how Windows handles deletion of directories that are still in use, but
on Unix a pg_ctl stop would no longer suffice to get rid of the old
postmaster, because after the rm -rf you can no longer get to the
directory in which the old postmaster is running.  You might be best
advised to reboot.)

            regards, tom lane