I see two possible reasons for this:
1–It is possible that you did not “Prepare” the project before you selected “Burn”. Preparing the project creates a folder and files. When you choose to burn the DVD, DVD Architect looks to these files (VIDEO TS and AUDIO TS folders with video and audio files) to burn the DVD.
2–If you already Prepared the project, it is possible that the folder you are directing DVD Architect to look at is not where the prepared files are located. Immediately after you click “Make DVD” and “Burn” you must click “Browse” and choose the correct “Prepared folder”, which contains the VIDEO TS and AUDIO TS folders for your project. It might be called something like “My DVD” unless you changed the name to something else. If you did Prepare the project, but do not remember, or do not know where the files were prepared too, look under the “Burning” tab located in “Prefrences” under “Options”. The Default prepare folder is listed. If that is not the folder, you can search your computer for folders with the names “VIDEO_TS” and “AUDIO_TS”.
I hope this helps,
Michael M.