AVStoDVD conversion software error message.

Hi, while converting one of my file to DVD I got the following error message from AVStoDVD software.
I am using AVStoDVD on a Windows seven 64 bit PC.
I have been successfully installed and used this software for some months now.
I can still use this to make DVD for other files.
Can some one please tell me, what does this error message mean?
And what is causing this problem?

Warning! DVD parsing aborted!
Error 52
Dateiname oder -nummer falsch
