I uploaded some video files from my Sony digital camera a couple months ago and I know I could open them up and view them then. But now when I try to open the files they converted to a THM File. I've tried several media player to open them with and they come up and say that they don't support that file type. (Windows media player, Real player, Nero Show Time, etc.). Nero Show Time will open them up as a thumbnail but not a video file. I found free software called Extension Changer and that didn't work. I called Sony, no help. I have about 30 family videos that I would like to open. Can you please explain in detail how to convert my files back to video format? I will send you one of the files and maybe you will have better results. I just don't know what to do. Please help me.
Can they be converted back to video format? Maybe you can suggest software. Thanks
Teddi

Hello, teddi54, and welcome to our forum!

The THM extension is listed as a Canon G3 or Olympus Digital Camera Thumbnail, Sony Ericsson Theme File, Serif DrawPlus Theme, or generally, a video thumbnail file. Thumbnails are small representative images of a larger image. Most standard digital camera images are .jpg format. Check the manual for your camera and see if they have any comments on what may have happened. Since many THM image files are renamed .jpg or .tiff files, try opening one in IrfanView. If it recognizes the file as a modified form of a more standard one, it'll open a window telling you so, and offering to correct the extension for you. If you don't have Irfan, you're missing a real treat in a small, free, and fast image viewer.