Lumia Video Trimmer is able to trim all clips captured with your Lumia device. Commonly these are H.264 with an .mp4 container. You can't trim a video which you have downloaded from web. Most likely it probably is not in the right format.
- How can I transfer music to my Lumia phone?
- Windows Phone app for Mac will not sync music on my Lumia phone. What should I do?
- What to check if I can't sign in or create the Microsoft account on my Lumia phone during the initial setup?
- How can I prolong the battery life of my Lumia phone?
- What are the other icons I see on the map in the Lumia Storyteller app?