How to correct tf8 "\x94"

Dear Sir or Madam,



Following error message appears when I check my website
http://www.kolaylezzet.com/



"Sorry, I am unable to validate this document because on line *517* it
contained one or more bytes that I cannot interpret as utf-8 (in other
words, the bytes found are not valid values in the specified Character
Encoding). Please check both the content of the file and the character
encoding indication.

The error was: utf8 "\x94" does not map to Unicode."



If it is possible, could you please explain what and how should be changed?



Best regards.