How do I add another FoE license to an established system?

Hi,

I have a 4 Server System with the following installed:

1. NPM, with P2 Failover license for the NPM and SAM (APM).

2. SQL Server with Neverfail Failover.

The other two Servers are the Failover machines!

I have an EOC license, and an EOC failover license I want to install on the system. EOC and it's licensing can be installed fine, but I can't seem to be able to add the FoE key, bearing in mind FoE is already installed.

I don't want to start "trying" things as this is a live system, so just wanted to know if anyone has any thoughts!

Thanks in advance.

Mykie