Sidenote:
If you have only one outlook account and it has been setup then you don’t have to need to pass the email-id into “Account” Property and by default it will take “Inbox” folder into consideration, you can pass folder name only when you have other folders exists.
The save attachment activity should work, as you said you can use it in your home network so may be network restriction or rule is their very less chance but still.
So, you can try this post as well and let me know 
Regards…!!
Aksh