A strange issue that apparently was introduced with a recent update to Outlook and is easily replicated across different computers and networks.
If you click the drop down next to an email attachment and then choose "Save All Attachments", select all the attachments and attempt to save to a network location, nothing happens. However, saving each attachment one at a time, or saving to a local drive works without any issues.
I also found a consumer thread that details a very similar issue. https://answers.microsoft.com/en-us/outlook_com/forum/oemail-oattach/office-2016-cannot-save-multiple-attachments-to-my/6d507bdf-1ebc-4852-852e-04a57f09c07f
Any ideas? I have a corporate client that regularly uses the feature and they're not very happy.