Crawl distributed file system error: The object was not found

SharePoint 2013 Standard server.

We have a a distributed file system (DFS) which I want to crawl.

I use a UNC path like:

\machine1234\Departments\HR 

The account that runs the crawler can access it. I tested by logging in with that account and pasting the above path into explorer.

I run the a full crawl and get the following error message:

The object was not found

I run with and without proxy, same difference. Any ideas?