Error Message: ERROR: CREATE USER: permission denied

-- System Information --

Platform: Windows 2000
Version: 5.0
Build: 2195 Service Pack 4

-- Application Information --

Name: pgAdmin II
Version: 1.6.0
Descripton:

Name: pgSchema
Version: 1.6.0
Descripton: PostgreSQL Schema Objects v1.6.0

-- Database Information --

Version: 7.2.1
Descripton: PostgreSQL 7.2.1 on i686-pc-winnt-msdev, compiled by msdev 6.0

-- Driver Information --

Name: PostgreSQL
Version: 7.3.100
Descripton: PostgreSQL 7.2.1 on i686-pc-winnt-msdev, compiled by msdev 6.0

-- Error Information --

Description: ERROR: CREATE USER: permission denied
Number: -2147467259
Routine: pgAdmin II:frmUser.cmdOK_Click

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Insert your comment
please send me an answer of this error because i´m youst starting to use this sw and i really need to create and work with databases, my email is lorena_m_v(at)hotmail(dot)com or you can contact me at lorena_medellin(at)yahoo(dot)es, i will be greatfull if you can help me.