Really? Here is my go at your filename as a text string
>>> x = "X:\Users\Andy.Rowlands\AHR.Data\REF.Requests\August2016\DesMoines.Hickman86th"
File "<string>", line 1
SyntaxError: (unicode error) 'unicodeescape' codec can't decode bytes in position 2-3: truncated \UXXXXXXXX escape
Now that was in python 3.5... That pesky folder called users, sometimes does, sometimes doesn't get interpreted as a unicode literal. I suspect
you are using python 2.7 which cleverly masks this flawed folder location for most things.
As a check, try moving your files out of anything that begins with a python literal... such as \t, \n, \U, \u etc,,, there are several.
If X is you working folder... and you have permissions, setup a folder structure that doesn't have those issues, doesn't have periods or spaces
and to be sure preface with an r for raw encoding.