I used to be able to drag and drop a file (PDFs) from my main PC to a 2nd PC, and drop them straight into Outlook as an attachment to an email. I had to reformat the 2nd PC and reinstall everything, and now, I can only drag and drop to a folder on the 2nd PC, and not into Outlook. If I attempt to drop it into an email in Outlook, the file ends up orphaned in a folder C:\ProgramData\MultiplicityTemp2
Both PCs run Windows 10 x64, with Office 2016 on the 2nd PC.
I vaguely remember having this problem before but I can't remember the solution. I've tried running Outlook as the administrator. I tried rebooting both PCs. I think it was a registry setting but I can't remember.