Win2PDF 7 uses a component of the Microsoft XPS Document Writer.  If the Microsoft XPS Document Writer is damaged or missing, it will cause problems with the Win2PDF installation.  Reinstalling the Microsoft XPS Document Writer usually resolves these issues.

If you install the free Microsoft "XPS Essentials Pack", it will install the Microsoft XPS Document Writer on Windows XP. You can download the "XPS Essentials Pack" from the following page:

http://www.microsoft.com/downloads/details.aspx?FamilyId=B8DCFFDD-E3A5-44CC-8021-7649FD37FFEE&displaylang=en