You have assumed correctly she too has Windows 7 with IE11
1) Using BT.com to access email
2) The BT Yahoo Mail has now transferred to new BT Mail, as was asked when she logged into the BT Yahoo Mail as usual
3) PC has all latest updates as they are set to automatically update
It is very odd as when she clicks to open a folder to access the saved emails only once did a folder show the saved files!
I will be going over to my friend this afternoon and check again and try on different browsers and possibly Thunderbird