Some videos that I made on Windows XP with Windows Movie Maker, won’t play online (especially for those with VISTA). I embed these videos and slideshows into webpages without using HTML because some people I design for, want to be able to make quick changes to the webpages. Why are some computers able to load and show the videos, while others only see a black panel? Is it the software (WMM, is it an issue with the file size, is it an HTML issue, or is it that VISTA and XP programs are still just incompatible? Is there software for slideshows, SWF, and similar files that I can use that will be compatible with all computer users online? Ive been told that it’s not incompatibility issues between XP & VISTA by some and told that it is by others – please advise.