Florin

First try this: remove the battery and charger (both) so the laptop do NOT have any power suply. Then press the power button for 120 seconds (2 minutes). After this put back the battery and try switch on. What this procedure do? It eliminate all residual curents from motherboard. Try to hear the fan, the HDD, and , in case you hear any conect the laptop to an external display.

FIRST you need to know with WHAT carrier was activated, than we may try remove. What we do actualy? We contact carrier and remove blacklist from server on IMEI base.