question about installation PostgreSQL

Dear list

I face with some problem in installation PostgreSQL 8.3 on winXP , long time
before I used PostgreSQL and PostGIS for managing shape file data. Last week I
tried to install PostgreSQL 8.4, after that I removed PostgreSQL 8.3 (I only
uninstalled inside windows control panel/add and then I deleted all folder
inside window programs) and I reinstalled PostgreSQL 8.4, and problem was
starting happen from this step, until now, I could not connect data by my user
and password or start PostgreSQL8.4 service from Administrative Tools . Even I
tried to uninstall and reinstall for at least 20 times, delete folder, remove
user/password on Administrative Tools.

Could you please help me to fix my problem

So today I tried several of time as bellow

1.Add/remove PostgreSQL
2.delete postgres user and pass by NET USER postgres /delete
3. delete folder of postgreSQL
4. Delete in side regiter of winXP in
side KEY_LOCAL_MACHINE\SOFTWARE\PostgreSQL\Installations\

But when I install it still got errors as the detail in install-postgresql.log,
I added some few line of the last install-postgresql.log file

Starting the database server...
Executing cscript //NoLogo "C:\Program
Files\PostgreSQL\8.4\installer\server\startserver.vbs" postgresql-8.4
Script exit code: 0

Script output:
Starting postgresql-8.4
Service postgresql-8.4 started successfully
startserver.vbs ran to completion

Script stderr:

Loading additional SQL modules...
Executing cscript //NoLogo "C:\Program
Files\PostgreSQL\8.4\installer\server\loadmodules.vbs" "postgres" "****"
"C:\Program Files\PostgreSQL\8.4" "C:\Program Files\PostgreSQL\8.4\data" 5432
"1"
Script exit code: 0

Script output:
Installing pl/pgsql in the template1 databases...
Executing 'C:\DOCUME~1\quang\LOCALS~1\Temp\radEC6B1.bat'...
psql: could not connect to server: Connection refused (0x0000274D/10061)
Is the server running on host "???" and accepting
TCP/IP connections on port 5432?

Installing the adminpack module in the postgres database...
Executing 'C:\DOCUME~1\quang\LOCALS~1\Temp\radEC6B1.bat'...
psql: could not connect to server: Connection refused (0x0000274D/10061)
Is the server running on host "???" and accepting
TCP/IP connections on port 5432?

loadmodules.vbs ran to completion

Script stderr:

[15:40:28] Write the data directory to the ini file...
[15:40:28] Write the port number, service ID, locale and superuser to the ini
file...
[15:40:28] Write ServiceID(postgresql-8.4) to registry/ini...
[15:40:28] Write Superuser to ini file and windows registry...
[15:40:28] Write Service Account to ini file and windows registry...
[15:40:28] Write the server description to the ini file...
[15:40:28] Write the server branding to the ini file...
[15:40:28] Write the 'whether stack-builder is disabled or not' to the ini
file...
[15:40:28] Finished running post-installation/upgrade tasks.
Creating Uninstaller
Creating uninstaller 25%
Creating uninstaller 50%
Creating uninstaller 75%
Creating uninstaller 100%
Installation completed
Log finished 05/17/11 at 15:40:38

And when I started server by using pgAdim the server response as below:

Server doesn't listen

the server doesn't accept connections: the connection library repots

could not connect to server: Connection refused (0x0000274D/10061)Is the server
running on host "127.0.0.1" and accepting TCP/IP connections on port 5432?

Thank again and very sorry for this very long question

Many thanks

T.X.Quang.