04-03-2018 06:40 AM
Received new Lenovo T470 with Sierra Wireless EM7455 and booted it. Default windows drivers for the WWAN, so I downloaded latest Sierra Wireless drivers from Lenovo's website (NZ3WN03W 17.11.0130.37). Installation was going fine, but when the installer prompted "Configuring your mobile broadband device - 68% complete. Do not shutdown or restart Windows" the system BSOD'd and now I cannot get the drivers to install - swmbbser01.sys will not load and only windows drivers are used even after completely uninstalling the drivers and removing any devices or pnp driver store packages via devcon. The laptop came with a restore point but it seems like it's corrupted and I can't revert to that state.
Does anyone know of a reliable way to get the drivers to install cleanly?
I have tried power cycling the card by disabling internal battery in the BIOS
Solved! Go to Solution.
04-03-2018 10:25 AM
Do it well, worse becomes itself
04-03-2018 10:39 AM
Thanks for the reply.
The laptop boots fine, and I understand the reason for the crash - let's just ignore that for now, I'm just trying to get the card back in a state where the SW drivers install properly. Is it possible to flash the firmware on the card using the "SwiFwUpdateUI.exe" tool distributed with the installer? Running this tool does nothing and there appears to be no documentation included.
I've tried manually installing the INFs, adding and removing Sierra devices, cleaning registry and folders, for two days now and the swmbbser01.sys refuses to load, even though its service (swmbbser01) is running and everything else appears to be correct. I have not been able to get the "Configuring your mobile broadband device - XX% complete. Do not shutdown or restart Windows" prompt again, except on the initial install where the crash occurred.
After uninstalling everything and then reinstalling, the Sierra devices include: (1) a network adapter that uses windows drivers (vwifibus.sys, wmbclass.sys on top of generic composite class driver), and (2) a composite device operated by generic class driver (usbccgp.sys) on top of the bus hub driver (usbhub3.sys). The Sierra modem port device does not exist and if I try to install it manually ("devcon install swmbbser01.inf @USB\VID_1199&PID_9079&MI_00") the port device and two other "unknown devices" appear with exclamation points in device manager with "device cannot start" status and various generic explanations - "cannot locate drivers" and "invalid function".
One thing I noticed is the instance ID string "MI_00" for the composite device hardware ID in the INF (swmbbser01.inf) does not match what devcon displays for the instance ID of the composite device windows is operating ("MI_0C"). That tells me that Windows can't find the driver because the hardware ID is wrong in the INF.