Connecting 2nd USB monitor disconnects DVI monitor
 

When I connect a second USB monitor, one of my monitors connected to a DVI port is disconnected. The only way I can reconnect the DVI monitor is to disconnect both USB monitors. How do I prevent the DVI monitor from being disconnected? The details of my configuration follow below. Thank you for your help.

Dell E6430 laptop connected to docking station
NVIDIA NVS 5200M – Driver version 9.18.13.697
Windows 7 64-bit
Display Link adaptor: Startech USB32HDDVII – Chipset: DisplayLInk - DL3900
Display link software version 7.1M1
Two monitors connected to each of the DVI and HDMI ports on the Startech
The configuration works fine with only one monitor connected to the DVI on the Startech
The problem occurs when I connect a second monitor to HDMI port on the Startech

more information
 

My problems go away when I close/move applications on the HDMI monitor before I close the connection to the HDMI monitor.