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What is an APPLICATION File?

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Question: What is an APPLICATION File?

Did you find an APPLICATION file on your computer and wonder what program should open it? Maybe someone emailed you an APPLICATION file but you're not sure how to use it. Perhaps you tried to open the APPLICATION file but Windows told you that it could not open it.

Before you can open an APPLICATION 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 .APPLICATION file extension refers to.

Answer: A file with the APPLICATION file extension is a ClickOnce Deployment Manifest file.

Other types of files may also use the APPLICATION file extension. If you know of any additional file formats that use the .APPLICATION extension, please let me know so I can update this information.

How To Open an APPLICATION File

The easiest way to open an APPLICATION file is to double-click on it and let your PC decide which default application should open the file. If no program opens the APPLICATION file then you probably don't have an application installed that can view and/or edit APPLICATION 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.

APPLICATION files are XML-based, text-only files meaning a text editor should be able to properly display the file's contents. You can learn more about XML files here: What is an XML File?

ClickOnce is a Microsoft system and they have more details about this type of file here: ClickOnce Deployment Manifest. Technically, the Microsoft ClickOnce Application Deployment Support Library is the name of the program that opens APPLICATION files.

If you find that an application on your PC does try to open the APPLICATION file but it's the wrong application or if you would rather have another installed program open APPLICATION 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 APPLICATION File

There are two main ways to attempt to convert an APPLICATION file to another file type:

The first option involving opening the APPLICATION 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 APPLICATION files, a third-party file conversion tool (the second option) could be very useful.

Important: You cannot usually change a file extension (like the APPLICATION 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 APPLICATION 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 APPLICATION file and I'll see what I can do to help.

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