C file icon

C File Extension

C/C++ Source Code Format

What is C file?

.C is source code file for C or C++ language. C and C++ is object oriented programming languages and are considered as medium level programming languages used for development of software applications. The C++ toolkit used for writing C++ code uses a notepad for writing the code and C++ compiler which converts the text file into source code along with other tools. Files with .C file extension are accessible with text editors and a user can read or write the data in these files through simple text editor software. The .C file contains actual code written by the user and other information such as directives and comments.

Programs which support C file extension

The following list contains programs grouped by 3 operating systems that support C files. Files with C suffix can be copied to any mobile device or system platform, but it may not be possible to open them properly on target system.

Updated: 02/26/2024

How to open file with C extension?

There can be multiple causes why you have problems with opening C files on given system. Fortunately, most common problems with C files can be solved without in-depth IT knowledge, and most importantly, in a matter of minutes. The list below will guide you through the process of addressing the encountered problem.

Step 1. Install Microsoft Visual Studio software

Install software to open C file The most common reason for such problems is the lack of proper applications that supports C files installed on the system. This one is an easy one. Select Microsoft Visual Studio or one of the recommended programs (for example, EditPlus, Borland C++, Eclipse IDE) and download it from appropriate source and install on your system. On the top of the page a list that contains all programs grouped based on operating systems supported can be found. One of the most risk-free method of downloading software is using links provided by official distributors. Visit Microsoft Visual Studio website and download the installer.

Step 2. Check the version of Microsoft Visual Studio and update if needed

Update software that support file extension CIf you already have Microsoft Visual Studio installed on your systems and C files are still not opened properly, check if you have the latest version of the software. Sometimes software developers introduce new formats in place of that already supports along with newer versions of their applications. This can be one of the causes why C files are not compatible with Microsoft Visual Studio. All of the file formats that were handled just fine by the previous versions of given program should be also possible to open using Microsoft Visual Studio.

Step 3. Associate C/C++ Source Code Format files with Microsoft Visual Studio

If you have the latest version of Microsoft Visual Studio installed and the problem persists, select it as the default program to be used to manage C on your device. The method is quite simple and varies little across operating systems.

Associate software with C file on Windows

Change the default application in Windows

  • Right-click the C file and choose Open with option
  • Select Choose another app → More apps
  • To finalize the process, select Look for another app on this PC entry and using the file explorer select the Microsoft Visual Studio installation folder. Confirm by checking Always use this app to open C files box and clicking OK button.
Associate software with C file on Mac

Change the default application in Mac OS

  • From the drop-down menu, accessed by clicking the file with C extension, select Information
  • Find the Open with option – click the title if its hidden
  • From the list choose the appropriate program and confirm by clicking Change for all....
  • Finally, a This change will be applied to all files with C extension message should pop-up. Click Continue button in order to confirm your choice.

Step 4. Verify that the C is not faulty

If you followed the instructions form the previous steps yet the issue is still not solved, you should verify the C file in question. Being unable to access the file can be related to various issues.

Check C file for viruses
1. The C may be infected with malware – make sure to scan it with an antivirus tool.

If the C is indeed infected, it is possible that the malware is blocking it from opening. It is advised to scan the system for viruses and malware as soon as possible or use an online antivirus scanner. If the scanner detected that the C file is unsafe, proceed as instructed by the antivirus program to neutralize the threat.

2. Check whether the file is corrupted or damaged

If the C file was sent to you by someone else, ask this person to resend the file to you. During the copy process of the file errors may occurred rendering the file incomplete or corrupted. This could be the source of encountered problems with the file. If the C file has been downloaded from the internet only partially, try to redownload it.

3. Ensure that you have appropriate access rights

Sometimes in order to access files user need to have administrative privileges. Log in using an administrative account and see If this solves the problem.

4. Make sure that the system has sufficient resources to run Microsoft Visual Studio

If the system is under havy load, it may not be able to handle the program that you use to open files with C extension. In this case close the other applications.

5. Ensure that you have the latest drivers and system updates and patches installed

Regularly updated system, drivers, and programs keep your computer secure. This may also prevent problems with C/C++ Source Code Format files. It is possible that one of the available system or driver updates may solve the problems with C files affecting older versions of given software.

Do you want to help?

If you have additional information about the C file, we will be grateful if you share it with our users. To do this, use the form here and send us your information on C file.

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