A file with the CAMREC file extension is a Camtasia Studio Recorder file. You can play CAMREC files with Camtasia Studio but unfortunately it comes with a 30 days time trial. So if you are not willing to buy this software just to play CAMREC files a better idea would be to convert it to any other popular video format. You can easily convert CAMREC files to AVI. Download the time trial version from their website and use the "Extract Camrec Contents" (shown in below image to) . This will extract all the resources in CAMREC file with .WAV file embedded in it. Now you can use any popular free video converter to converter to covert the .WAV file to desired format. Even .WAV file itself can be played on any video player.
You can use FormatFactory to convert AVI files to other formats.