Hi grahamd22
Yes, you're going to need to use group policy to lock the machines down, since Impero doesn't tend to replicate things which can be done via group policy. Impero will run quite happily side by side with Ranger and all the other software you mentioned, so you could run them together and phase Ranger out gradually. Impero does have a bulk user creation tool you can request (not sure about mailbox creation), or you could use something like AD Infinitum.