MC92N0 loss of configuration after a cold reboot


We are facing an issue with our MC92N0.

After a cold reboot, the WIFI is back ok, but the date, icone on desktop and Naurtech configuration are lost.

We are on Windows CE 7 with the last update 07.57.34 / 07.00.2864.

Date are important for us as we connect to a server with certificate.

Icon too as we've delete all unecessary ones on the dektop for our users.

And Naurtech config to access our software.

So it's quite painfull.

Do you have any idea how to solve this issue?