People app exits when trying to add or edit a contact

[Windows Central Question]

I can view accounts from facebook and skype but not outlook.com. I add it as an account and get a success message but don't see it in the list "show contacts from" in the filter page.

When trying to add or edit an account the app simply exits and leaves me on the start page.

Phone is 640XL - worked fine until I upgraded from 8.1 to 10 the other day.

Would be grateful for any assistance.