Hi faizah,
1. Are you able to install other program on the computer?
2. Have you made any recent changes on the computer?
3. Is this the first time you are installing the program?
Runtime errors can occur if you are running two software programs that are not compatible, if your computer has memory problems, or if the computer has been infected with malicious software.
For more information on runtime errors refer the below link
What is a runtime error?
http://windows.microsoft.com/en-US/windows-vista/What-is-a-runtime-error
If you are installing the program for the first time check system requirement for the program on the vendor website.
For additional support try posting your query in the postgrespl forums and check.
http://www.postgresql.org/community/
Hope this helps!
Halima S - Microsoft Support.
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