ok so it was working and then on my site it stopped working. or rather the site stopped functioning properly.. i couldn't log into via the wp-admin.. so after some hunting i switched off (by moving to another folder) all of my plugins.
ok now wp-admin works and i no longer get the white blank screen..
and the as i reinstalled and activated each plug in i tested..
there are a few that break the site.. photo dropper, keirellians sitemap and redirection... and redirection is the one that really hurts because i use it a lot..
i have dan raines silo builder plugin and maybe that is the problem.. and i have a lot of others.. so tommorrow i'll turn em all off again and start with just redirection to see if it is the culprit or if its a clash with some other plug in.. but fior now its broke..