What is a CLN File? Did you find a CLN file on your computer and wonder what program should open it? Maybe someone emailed you a CLN file but you’re not sure how to use it. Perhaps you tried to open the CLN file but Windows told you that it could not open it. Before you can open a CLN file (assuming it’s even a file format that’s intended to be viewed or edited), you’ll need to determine what kind of file the CLN file extension refers to.Answer: A file with the CLN file extension is a Backup Configuration file. Other types of files may also use the CLN file extension. If you know of any additional file formats that use the CLN extension, please let me know so I can update this information.How to Open an CLN File: The easiest way to open a CLN file is to double-click on it and let your PC decide which default application should open the file. If no program opens the CLN file then you probably don’t have an applica