FRAMEMAKER "Unable to open file" when using the TRAVELDITA XML example files

Hello All,

Please avdise ...

When I try to open and XML file in the DITA example fm set (TRAVELDITA) in ..

C:\Program Files (x86)\Adobe\Adobe FrameMaker 2017\Structure\xml\TravelDITA

I get an error message stating "Unable to open file!" and "Try opening it manually and checking for errors". 

How should I open it manually? What errors should I look for?

I also tried coping TRAVEL DITA from another colleague's machine but still the same problems. 

Thanks

Roy