Postgresql server fails to start autmatically some days after installation.

Hi,
I am a novice to postgresql. I needed a local database server on my company laptop running on Windows XP. I got postgresql 9.1 installed on it.
For a few days it worked well, but after some 5-6 days, it failed to start on system restart. Gave following error:
Server doesn't listen
The server doesn't accept connections: the connection library reports could not connect to server:
Connection refused (0x0000274D/10061) Is the server running on host "localhost" (127.0.0.1) and accepting TCP/IP connections on port 5432?

I saw in the windows 'services' tab, that postgres sql service was stopped.
The 'services' window shows that it has been set to start automatically, but that it has been stopped. If I try to start it there, it shows 'Error 5: Access is denied'.

I don't have administrator privileges as it is a company owned laptop. However, I tried to get it restarted from technical help desk personal who has administrative privileges (We Run it as different user with administrative privileges. We can't do 'run as administrator' as the administrator password is open to none as a company policy.) It still showed Error 5.
I also tried to change the port using hba_conf, but no benefit.

Finding no solution, I got it reinstalled on a different port (5433), and it again worked well for a few days.
Today when I tried to connect to the database, it again showed the same issue. Server doesn't listen. Could not start service. Etc..

What I fail to understand is that why it works fine for some days, and then one fine day it fails to start.
Mine is a windows Xp 32 bit system with McAfee and other software installed. I have windows regular updates and various software and security patches constantly updated.

Can you please help me identify the problem and fix it?
Please keep in mind that I do not have administrative priveleges. I can only seek an administrator to make system changes on special request.

Thanks and Regards,
Karan Bansal

American Express made the following annotations on Tue Sep 25 2012 04:17:32

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