cannot find name for user ID

Hello,

I have newly installed cygwin on Win200 PC, but the it always start
with:

"id: cannot find name for user ID 36987"

and I fail to initialize PostgresSQL with this message:

"The program
    '/usr/bin/postgres'
needed by initdb does not belong to PostgreSQL version 7.3.4 or
there may be a configuration problem.

This was the error message issued by that program:
/usr/bin/postgres: invalid current euid 36987"

I have uninstalled and reinstalled cygwin but the problem remains
unsolved.

Please advice m(__)m

Thank you in advace.

Hisao
chida.A28990@canon.co.jp