Can't login using Firefox, Chrome, or Safari - Login works for IE 9

I am using NOPCommerce 1.90 with IIS v.6. I am using cookies to store login information from another site. I am able to access NOP just fine with IE 9. But if I use any of the other browsers I am redirected to NOP but it is not seeing my login. I have been digging through the forums for 2 days now trying everything under the sun. If anyone has any ideas or thoughts on what I may be missing or what the issue may be it would be greatly appreciated. Thanks in advance!

I found out what the issue was. Another programmer commented out the key within the other program ans I was not aware of it. Once I corrected that the login functionality was restored.