InfoPath Dev

I can't open an XML file with InfoPath because it tells me that it is not an InfoPath file. When I try to use ''Open With...'' I get this message: ''InforPath cannot open the following file: <file name>. The file does not appear to be an InfoPath form. The when I open the details it reads: ''The processing instruction in the file is missing ...

Hello! I have been messing around with InfoPath with the help of the book from MS Press by Roger Jennings. I have been having some problems opening XML files with InfoPath because I have XMLSpy installed on my computer. Is there anyone out there who knows of conflicts between these two programs?