Please note that when using the API getOptionChain with XML, if you copy and paste an option symbol within a browser, the extra spaces are not added properly. Option symbols start with '@" and require six characters afterwards. Additional spaces are added to the option symbol if the symbol isn't six characters in length. For instance MSFT is only four, which requires two spaces added to the end.
As you are not able to copy and paste the correct Option symbol from XML in a web broswer, use a JSON request instead. The JSON output does have the correct spaces allowing you to copy and paste into another API in your web browser.