ENA driver 2.2.3 won't install on server 2008r2

I'm trying to upgrade a T1.micro server (2008r2) to a t3.small, which needs the ENA network driver installed. In the documentation, the 2.2.3 driver is specified. I downloaded that driver and attempted to install it on the t1.micro server with powershell, which errors out with an incorrect operating system message.