Hi, I am a MS v15 user and just downloaded V18 but have issues getting the download sorted so looking for some help please. Having downloaded I noted a lot of files had been saved in my Onedrive folder. I have limited space in that folder ( free allocation) so moved those files. Other than that the download was fine. As a first trial I just tried previewing some videos and photos on my PC ( Import). Photos and older .wmv files previewed fine but if I tried to preview a MP4 file I only got audio but no video and the preview cursor stutters/staggers across the clip. I thought it might be a missing codec and I know the videos I created in V15 used Mainconcept so I downloaded that..........no difference. Any ideas please? (PS V15 still runs fine.)