php: SimpleXML Load File Invalid Character Error

Question

I have a php application which -sometimes- fails (depends on what data I load) and gives errors like:

parser error : PCDATA invalid Char value 11
Warning: simplexml_load_file(): ath>/datadrivenbestpractices/Data-driven Best Practices in 
Warning: simplexml_load_file(): ^ in 

I am certain that there are some values which are causing the problem. I don't have control over data. I have tried solutions from: Error: "Input is not proper UTF-8, indicate encoding !" using PHP's simplexml_load_string and How to handle invalid unicode with simplexml and How to skip invalid characters in XML file using PHP but they have not helped.

The culprit strings are: 'Data Driven - Best Practices' and 'Data-driven Best Practices to Recruit and Retain Underrepresented Graduate Students May 12, 2011 - 1:30-3:00 p.m., EST' (may be dashes or return characters).

What can I do? Mine is a Windows php test environment but the live environment will be a LAMP one--can 't touch the .ini files.

Thanks.