So, that's the reason for the login failed: either your account expired or you need to remove your accounts from accounts application and re-register? I already did remove the account and launched Wazapp again, as the warning at the beginning of this post suggests, but no positive result. I didn't do anything more drastical like removing .wazapp or even the .db file. I read of too many cases where this didn't work either. So, can I get to know what precisely to do?