Oracle application is not working on Windows 7 OS 64-bit version

I had the same problem and I was using IE8 and that caused the problem.
I have followed the below steps and got it to work

Try This .
This is how I got IE7 to work with Oracle forms: (IE8 will not work properly)

1. Add/Remove programs: Uninstall IE8 back to IE7, then reboot.
2. Add/Remove programs: Uninstall IE7 back to IE6, then reboot.
3. Add/Remove programs: Uninstall JAVA.
2. Add/Remove programs: Uninstall JInitiator.
3. Rename all remaining "jvm.dll" files on my computer to "jvm.dll.bak"
4. Reboot
5. Reinstall IE7 from clean install:

http://download.microsoft.com/download/3/8/8/38889dc1-848c-4bf2-8335-86c573ad86d9/IE7-WindowsXP-x86-enu.exe

6. Logon to Oracle to reinstall JInitiator, then close all IE7 windows.
7. Place the attached file "jvm.dll" in the following folder:

C:\Program Files\Oracle\JInitiator 1.3.1.24\bin\hotspot

8. Open your JInitiator control panel (located in Windows Control Panel), open the Advanced tab, verify the Java Runtime Environment displays "Use JInitiator Default".
9. Try to log into Oracle forms.
10. Good Luck!