Android map API earlier working key suddenly stopped working

I have used maps before in a small app and it was working fine and i wanted to use it again in another #android app using google API 2.1 update api level 7 emulator. The problem is that getFromLocationName() fu开发者_如何学Cnction is not working. The returned size of list is zero. After many hours, I used my friend's computer registered MAP API key. Then getFromLocationName is working but showing no tiles. I gave code to him and asked him to use his API key and same emulator and IT WORKED. I have checked my md5 has key again and checked generated key also. I tried to reopen previous working app and it is also not working now. I have also tried to use new emulator nothing works. Damn frustrated please help..

Have you tried signing the application with a release key (and corresponding api key ofc), and then validate it on the emulator?

It can give a good indication whether or not there's something wrong with your debug keystore.