Try to print again. Then, look in the log file to see what it says. There might be an obvious failure, like it truncated your printer name (if it was a really long printer name), or it substituted an underscore for a space, or some such. If the failure is not obvious, contact APPX Software Technical Support. We will probably want to see (via email) or hear (over the phone) the contents of the log file.

Remember to remove the WINPRINT_DEBUG variable once you have solved the printing error.