Dell Latitude E6420 with WWAN card Dell Wireless DW 5560 WWAN Mobile Broadband

Hello everyone,

I recently bought myself a used modem DW5560 for my Latitude E6420.

According to the modem page this modem is not for E6420 system but for some others (e.g. E6430). And of course the driver installation initially failed with error that Authentication failed and this device is not compatible with my system.

I did not give up. I found on Dell forums that I can still install the driver by copying driver files from temp folder and then install from unpacked raw driver files.

Done! Driver v 7.2.7.3 has been installed. "This device is working properly" message on device manager's area.

But still something is wrong... When I try to establish connection with my provider there is:

"Error 734: The PPP link control protocol was terminated."

And now i am out of ideas. Anyone able to point me where to go next? Maybe I need different driver files after all?