Please try everything to specify your installation and server settings. Because there is nothing but no admin login, it is difficult to give you any advice to solve the problem

I am withdrawing from this bug report since the problem has gone away, apparently caused by temporary failure of the contentbymail plugin and/or changes on my mailserver from the host.

www.joomlapolis.com/component/option,com_joomlaboard/Itemid,/func,view/catid,43/id,43702/#43702