Q:“But I don't have a a new thumbnail image created to upload. How do I create a new one?”
If your video imports without a thumbnail or you want to replace a thumbnail, you can capture a new image using the following steps:
First, play the video and pause it on the image you'd like to use as the thumbnail.
If you are using a Mac, open the Grab application (if you're not sure where that's located, just type Grab into the Spotlight search). Go to Capture in the menu bar and drop down to Selection. A text box will pop up instructing you to "Drag over the portion of the screen you want to capture." Click and hold the arrow at the corner of the image you want to use, then drag the red box that appears over the rest of the image so that it is outlined. When you release the mouse, your image will appear in an unsaved file. See if it's what you want, then save the file.
If you are using a Windows machine running Vista, open the Snipping Tool (if you can't find it, click the Start Menu and type Snipping in the search box). Once it opens, click the edge of the image you want to use and then drag the cursor over the area of the image and release. If you like the clipped image as it appears in a new window, then click save.
If you are running Windows but not Vista, you can use the Print Screen function and then crop your image in a tool such as Paint.
Once you have the new image saved, follow the steps above to upload it as a new thumbnail.
Magnify.net is the leading provider of cloud-based video curation solutions to the online publishing, non/profit, community and ad network markets. Magnify's solutions enable websites to curate, upload, and aggregate content. The Magnify curation solutions power the world's most engaging video websites.