Robocopy throws 'filename, directory name or syntax is incorrect' on local disk

I'm attempting to use robocopy to move files older than 5 years to another server, to reduce the size of a 3TB volume under 2TB so that the machine can be P2V'ed using Microsoft VM Converter.

There are actually 3 identical servers (3 offices for the same company), and this command has worked fine on 2 out of the 3. But when run on one server in particular, the output is The filename, directory name, or volume label syntax is incorrect

There are plenty of search results for this error on Google, but they all seem to deal with copying from/to network shares (either mapped or UNC). The output I'm getting indicates that robocopy is finding an issue with the local folder, which is concerning (and not in any search results).

Full input/output included below, but are there any suggestions for things I might be doing wrong, before I turn to CHKDSK? A full scan could take days and would slow access for all users, so I'd prefer to avoid it.

(Note: HP ACU says no disk/volume problems, and the disk does not otherwise indicate any error)

Input

robocopy D:\Local\Folder X: /e /z copy:DATSO /move /minlad:1800 /log:D:\robocopy.log /tee

Output

2016/01/10 20:32:23 ERROR 123 (0x0000007B) Scanning Source Directory D:\Local\Folder
The filename, directory name, or volume label syntax is incorrect.
Waiting 30 seconds...

Try adding the /NOCOPY flag to your copy command (see robocopy documentation). This will tell Robocopy not to try to read any extended attributes or alternate streams for folders.

Faling this, use PROCMON from Sysinternals and filter process robocopy.exe - this will give you more low-level diagnostics to explain what failed.