How can file paths be submitted in a form and not be received missing the backslashes that separate folders?

In one of my forms, we ask the user to submit the file path for a document. 

If the submits "\servername.com\folder_level1\folder_level2\folder_level3" this is what we receive: "\servername.comfolder_level1folder_level2folder_level3". 

How do I prevent the automatic removal of the backslashes?  Thanks.

UPDATE: I found a thread on this from Nov. of 2014: http://www.jotform.com/answers/464765-Backslashes-disappearing-from-text-on-form

Is this the only solution?  How can I reasonably expect a user to add additional backslashes to a file path they are submitting?

Unfortunately this is the current solution that will allow backslashes to be submitted without stripping them off.

You can add instructions telling the users to use double slashes

You can probably use a text-area input to accommodate for long folder paths

Grrr!

Thanks for the information.