While generating XML file, Error " 'ascii' codec can't encode characters in position 0-1:ordinal not in range <128>"

1. What is the problem? Be very detailed.
While generating XML file, we are getting the Error " 'ascii' codec can't encode characters in position 0-1:ordinal not in range <128>"
2. What app or server are you using and on what device and operating system? Include version numbers.
ODK Collect v1.24.1 on Windows Desktop PC having Windows 7 as Operating System
3. What you have you tried to fix the problem?

4. What steps can we take to reproduce the problem?

5. Anything else we should know or have? If you have a test form or screenshots or logs, attach below.

It would be better if you could attach your XLSForm here.