EC2 EIP Point to Private IP for Email Server purpose.

Hello Everyone,

Wondering if anybody would be able to share some information or guidance for below.

I had the EC2 instance up with AWS EIP, I loaded the email service/server software to the instance (windows server base). How do I point the EIP to AWS Private IP as I was able to access webmail from local network (AWS Private IP) but not able to access the webmail from EIP.

Thank you for your time looking into this matter.