Signed out of Microsoft acct at random

[eknirb]

Here's the story. I use Bing as the start page in FF. So see the box top right? I stay signed in to FB acct, but once in awhile, I get signed out of MS acct. No, it's not cookies- it happens on FF, Chrome, IE, Safari, Opera, I have 'em all. I write Bing help; believe me when I say they are not very bright. At least the ones that write me. The answer for everything is to 'optimize your browser' and 'clear your cache.'
So why do I get signed out?

 

[eknirb]

running Win 7 home premium

 

[A Guy]

Nice avatar and slogan under your name eknirb It may well be MS. They have recently changed security settings, and they may only allow you to be signed in for a certain period. Can you tell if the sign out is at a regular period, or is it random?

A Guy

 

[eknirb]

I will check about that. I haven't seen it happen once today. I am sure it is MS.