How To Delete Outlook Mail Account.

[MichaelZZ]

My bank has recently updated its mobile banking app such that it doesn't now work with my oldish Huawei smartphone which uses Android 4.2.2.
I have been given a Nokia Lumia 520 phone running Win 8.1. The banking app works fine on this phone but in order to open the required Microsoft Account I first had to set up a Hotmail / Outlook email account. Again I did this successfully.
However, my wife has had a Hotmail account for 3 or 4 years and yesterday she noticed that the emails she sent apeared to have been sent from her account but had been hijacked with my User Name. I have tried to access her and my profiles on Outlook but can't seem to change the sender name.
An alternative might be to delete my Outlook email entirely and start from scratch but I'm afraid I might just delete her Hotmail account into the bargain. This would not go down well!

Am I missing something?

[MichaelZZ]

I think I've sorted it, thanks to a YouTube video.