RobotStudio event

How to connect to > 1000 controllers? NetworkScanner / controllerFactory

I am using VB.Net with the PC SDK to get the messages from all the controllers (>1000) in our system. I use the NetworkScanner.AddRemoteController() to a the controller IP addresses. However once I add too many I get strange numbers of controllerInfo returned. 
I have scanning them in batches and restarting the "RobNetScanHost" service but then I get   'System.AggregateException'.
I am at a loss to see a way around this, I can't find a method of connecting to the controllers without networkScanner and I can't clear the scanner.
Please if anyone has any ideas of a way to achive this it would be a great help.

PC SDK version 6.04.01
Visual Studio 2013
OS Windows 7 Ent