After trying to get help from the reseller support (a famous laptop seller), I think the best way to find help about it is trying there... (the support still is fixing a broken link for update.. and don't seem to know what to do after update did not solve anything).
I'm using the last version of IntelProSet software to manage my wireless connections but for an unknown reason, the software don't keep profile after a windows reboot. I don't know anymore what to try after:
-Reinstalling before and after updating (from version 10.0.... to 10.5. ... and to 11.0.0...)
-Repairing installation many times.
-Trying chip upgrade from dell's site.
And unfortunately, no result are returned from search engines avec troubleshooting databases, so my last hope is there.
Thanks you in advance.