Verizon netbook VZAccess Manager error 678

Hi everyone,

I have a Gateway LT20 netbook running Windows XP Home.
It can connect to both wireless networks and 3G using VZAccess Manager.

It will still connect to wi-fi, but is used for on-call work and needs 3G connectivity more often. When I try to connect to Verizon 3G WWAN, I get Error 678 (Connection failed--the remote computer did not respond), or Error 721--the same connection failed message.

VZAccess Manager tells me I'n running the most recent version.
I've tried unistalling/re-installing VZAccess software.
My built-in modem device is using the most up to date driver.

Has anyone seen this? Or have any suggestions?

Thanks,