Duplicator is the most powerful migrator available. It enables you to:
Move, migrate or clone a WordPress site between domains or hosts with zero downtime
Pull down a live site to localhost for development
Transfer a WordPress site from one host to another
Manually backup a WordPress site or...
I think the best way to analyze ir is to set a local dev environment with xdebug and do some step debugging to see what happens, just for security I place rsfirewall system plugin to be the first plugin to run, by putting it on top of all other system plugins