postgres installer fails with comspec error even though it is correct

Hi,

I am trying to install postgres on windows 7 64 bit machine.
I get a COMSPEC error message.
I checked comspec using %COMSPEC%" /C "echo test ok and it looks okay.

Following is the detailed error message.

Executing C:\Users\tempuser\AppData\Local\Temp/postgresql_installer_f998810adb/temp_check_comspec.bat
Script exit code: 1

Script output:

Script stderr:
'"C:\Users\tempuser\AppData\Local\Temp\POA330~1\TEMP_C~1.BAT"' is not recognized as an internal or external command,
operable program or batch file.

Error running C:\Users\tempuser\AppData\Local\Temp/postgresql_installer_f998810adb/temp_check_comspec.bat : '"C:\Users\tempuser\AppData\Local\Temp\POA330~1\TEMP_C~1.BAT"' is not recognized as an internal or external command,
operable program or batch file.
The environment variable COMSPEC does not seem to point to the cmd.exe or there is a trailing semicolon present. Please fix this variable and restart installation.

Please let me know how to fix this.

Thanks,
Venkatesh