Shaun,
Make sure you generated correct Ibase for target system (Example- QR3 CLIENT 600). Check in managed system setup for system QR3 600 and re- try it.
*The Installed Base for all systems/clients assigned to the Logical Component (which is assigned to your Project) should exist. Please try to generate the IBase to all clients, review your Logical Component and try it
Thanks
Sateesh.