What is a CSR File?

How to Open, Edit, & Convert CSR Files

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

Before you can open a CSR 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 .CSR file extension refers to.

"What is a CSR File?"

A file with the CSR file extension is usually a Certificate Signing Request file.

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

How To Open an CSR File

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

CSR files are partially encrypted files that are used to help prove the identity of a website. CSR files can sometimes be opened with software such as OpenSSL or Microsoft IIS.

If you know of anything else useful about CSR files that might be good to include here, please let me know so I can update this page.

Tip: Use Notepad or another text editor to open the CSR 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 CSR files but it's worth a try.

If you find that an application on your PC does try to open the CSR file but it's the wrong application or if you would rather have another installed program open CSR files, see my How To Change the Default Program for a Specific File Extension guide for making that change in Windows.

How To Convert a CSR File

There are two main ways to attempt to convert a CSR file to another file type:

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

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

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