I am using Nokia E7 from last many months. May be around 4 months I am using this cell phone. For security purpose, I have installed an Anti-theft that is F-secure on my sim card which I was using. It is nice software which has kept my phone long away from many viruses and thefts. Currently I am on vacation and I am using a prepaid-card of a foreign country. My phone is working well but I am unable to install F-secure currently. It asks for a code and when I enter the correct code which I am sure about it, but still it is not deactivating. Should I need to insert my older sim card or do I need to be present to my home network for stopping this? Is there any solution?