Can get me.com emails on computer not tablet

My tablet says I need to put a password in for the server to get emails on it, but touching wood, my laptop and computer are not affected.

Also, I need to log back in to facebook on my computer, but can not for the life of me remember or even guess at the email address I used originally...Tablet and laptop are ok...

Any help please, or do I need a 7 year old?

edit: cracked the facebook thing....

My tablet says I need to put a password in for the server to get emails on it, but touching wood, my laptop and computer are not affected.

Also, I need to log back in to facebook on my computer, but can not for the life of me remember or even guess at the email address I used originally...Tablet and laptop are ok...

 

Any help please, or do I need a 7 year old?

edit: cracked the facebook thing....

Something to do with this?:

https://support.apple.com/en-us/HT204397

This is about application-specific passwords for accessing iCloud email. This support thread is a few months old but it appears Apple have now made it compulsory.