I have the same issue.
Dell Latitude E6430 Win7 x64
Dell Mobile Broadband Utility (AT&T) Novatel Wireless E371 WWAN
5/4/2012
Version 3.00.96 Build 007
Settings Version 1.60.330
SDK Version 1.02.20.002
Cisco VPN 5.0.7.029
Cannot access my network resources when using VPN through the Dell Mobile Broadband Utility. But it works perfectly fine with any WiFi connection. Is there an alternative to the Dell Mobile Broadband Utility by Novatel Wireless?
I contacted DELL GOLD SUPPORT and they were useless.