Email With 'datauri-file.gif' Attachments.

Windows 10..Edge...all up to date etc.
Better half receive an email from a trusted national organisation on her PC.
She downloaded the notice that was attached.
She then 'forwarded' the complete original email to some one else.

With no action on her part the 'forwarded' email had 5 mysteriously attached files as per the image below.
She could open each one of them and it was images of her 'Pictures'...thousands of them! Each of the 5 attachments are the same.

The person to whom the email was forwarded received the attachments but they were 'black boxes' and couldn't be opened.

I have Googled and apart from finding the same question I can find no explanation.
I have run Malwarebytes/Adwcleaner and my F-Secure scan with nothing found.

Sorry can't upload the image at the moment...it is an image of the bottom of the email showing 5 normal attachments each labelled ' datauri-file.gif'

Any ideas Please?

 

Sorry, my 'error' was a 'Snipping tool' image that I tried to upload with 'Postimage' then 'Imgur''
I believe there is no threat....I am using my own PC and my wife's PC has shown nothing odd apart from the question.
The image was transferred via a USB memory stick to my PC.

 

https://s20.postimg.org/f2pou5w8t/Z_EMail_images.jpg

This is the image I tried earlier....have now resolved how to post it!!
Please remove this post if required.
There seems to be no answer to my dilemma which seems to have been a one off!