Format and Indent Fails
Problem
When I use the 
Format
and Indent function, I get an error message that indicates the Format and
Indent failed.
Cause
This happens because the application tries to limit the exposure to XXE attacks so the parser blocks the expansion of system entities (the ones that are loaded from disk or from remote sources).
Solution
If you are in complete control of the XML documents (you manage or trust those who are creating and editing the documents), you can disable this particular check by selecting the Enable system parameter entity expansion in other entity definitions option in the XML Parser preferences page.