Did you find an FOS file on your computer and wonder what program should open it? Maybe someone emailed you an FOS file but you're not sure how to use it. Perhaps you tried to open the FOS file but Windows told you that it could not open it.
Before you can open an FOS 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 .FOS file extension refers to.
Other types of files may also use the FOS file extension. If you know of any additional file formats that use the .FOS extension, please let me know so I can update this information.
How To Open an FOS File:
The easiest way to open an FOS file is to double-click on it and let your PC decide which default application should open the file. If no program opens the FOS file then you probably don't have an application installed that can view and/or edit FOS files.
Warning: Take great care when opening executable file formats received via email or downloaded from websites you're not familiar with. See my List of Executable File Extensions for a listing of file extensions to avoid and why.
As of this writing, I don't have information on any specific applications that will view FOS files or open FOS files for editing. If you know of any, please send me a quick email and let me know the name of the program so I can update this page.
Tip: Use Notepad or another text editor to open the FOS file. Many files are text-only files meaning no matter the file extension, a text editor may be able to properly display the file's contents. This may or may not be the case with FOS files but it's worth a try.
If you find that an application on your PC does try to open the FOS file but it's the wrong application or if you would rather have another installed program open FOS files, see my How To Change the Default Program for a Specific File Extension guide for making that change in Windows.
How To Convert an FOS File:
There are two main ways to attempt to convert an FOS file to another file type:
- Open the FOS file in its default program and choose to save the open file as another file format.
- Use a File Conversion Online Service or Software Program to convert the FOS file to another file format.
The first option involving opening the FOS file in its native program is preferable because it's both easier and will probably result in a more accurate file conversion. Of course if you don't have a program that opens FOS files, a third-party file conversion tool (the second option) could be very useful.
Important: You cannot usually change a file extension (like the FOS file extension) to one that your computer recognizes and expect the newly renamed file to be usable. An actual file format conversion using one of the methods described above must take place in most cases.
Still Having Problems Opening or Using an FOS File?
See Get More Help for information about contacting me on social networks or via email, posting on tech support forums, and more. Let me know what kinds of problems you're having with opening or using the FOS file and I'll see what I can do to help.