Jaspersoft Server 6.2 LDAP authentication Spring Security Check Balnk Page from AWS EC2 instance

We have Jaspersoft Server 6.2 installed in AWS EC2 instance. We are trying to implement AD authenticaiton usig LDAP. While trying any login, we are getting "jasperserver-pro/j_spring_security_check" blank page. A same Jaspersoft 6.2 server using the identical configuration file works really well within our company domain. We have change the security settings like allowed all TCP/IP traffic in both Inbound and outbound, disabled firewall but still facing the same issue.

Anyboday has any idea of why this is happening in AWS EC2 not it our local server? Please help me.