EM7455B in Panasonic Toughbook FZ-55

I have a Panasonic FZ-55 laptop with a factory integrated EM7455B, running Win-10:
a) EM7455 s/w version SWIC 9X30C_02.24.03.00
b) Win10 version 20H2 Build 19042.1110

At laptop boot the EM7455 will refuse to establish a data connection:
a) SIM is valid
b) Full network coverage
c) Static location (i.e. not moving around)
d) Windows->Network and Internet->Mobile shows that the EM7455B is registered onto the VodafoneUK network.
e) Upon trying to establish a data connection (to the APN), Windows immediately shows error “Can’t connect to this network”.

Once the EM755 is in this state the only way to correct it is to manually disable the EM7455B in Device-Manager and then re-enable it.

It is as though Windows has some incorrect SIM/APN information at boot? And only after a cycle of the EM7455B does it get corrected?
Anybody seen similar issues?

Hi dh29,

Sierra doesn’t provide any product named EM7455B. It seems to be a variant of EM7455 which is for a specific customer.

In this case, you shouldn’t install any firmware on Sierra Wireless source page. Just try to install the latest drivers on the Panasonic page. If the issue still happens, please contact them for support.



Hi jedung,

Thanks for your reply and advice.

It seems this issue is related to Windows, so I probably shouldn’t be posting on the Sierra Wireless forum, but was stuck!

I may have had a bit of success yesterday… By disabling Windows ‘Fast Start-up’ within the Power Control options (Control Panel->Hardware and Sound->Power Options->System Settings) this appears to have resolved the issue.