I've downloaded firefox on my MI4C and added the AdBlock Plus addon. I think it was after that, that random popups appeared and in any browser some advertisement side opened, without anything I did. I deleted every app, cleared app caches and the system cache, tried several anti-ad and anti-virus apps... nothing helped. Now I went to settings and Reset my phone. Somehow this changed the ad-ware, but didn't get rid of it. I still get those strange popups with the message: "This app is financed by Advertisements.... " and two buttons "Cancel" and "Accept". I cancel those, but it pops up nearly every minute, which makes using the phone a mess. How can I really reset my phone? Preferably I'd like to wipe all data and reset to factory default (international software). I only need english language support, but the EU version (with german) would be nice. Also I need the google app store. Could someone give me a tip, how I can reset/update/wipe my phone? Thanks in advance for any help!