Why does my Lumia 535 want an Outlook password every time I try to access Cortana or d/load app?

[WPCentral Question]

Lumia 535 wants an outlook password every time I try to access Cortana or d/load app

I have had the phone for 3 months and this has never happened before. I am not aware of ever having an outlook login. I do have a microsoft password for my PC but I have tried this password and it does not work here on my phone. There is no facility to change or reset this password. The only two options are save or cancel. Any suggestions as to why this is happening now?