Tips to open FSI file

Can't open the FSI file? You are not the only one. Thousands of users face similar problems every day. Below you will find tips on how to open FSI files as well as a list of programs that support FSI files.

FSI file extension

File Name Visual F# Signature Format
File Developer Microsoft
File Category Developer Files

The FSI file is supported on 3 operating systems. Depending on your operating system, you may need different software to handle the FSI files. Below is a summary of the number of programs that support and open the FSI file on each system platform.

Operating systems
  • 4
  • 1
  • 2
  • 0
  • 0
  • 0

What is FSI file?

The file with the extension FSI is the Developer Files file type. The creator of this file is Microsoft. Additionally, the Developer Files category contains 1205 of other files. Visual F# Signature Format is supported by 3 operating systems. Although it can be found with greater or lesser success on any operating system, it will only be useful on Linux, Mac OS, Windows. The main program that supports this format is Microsoft Visual Studio. This was created by Microsoft Corporation. This file type can also be opened by 6 other programs. You can use TextEdit, Windows Notepad, Nvu, NotePad++ text editor in case Microsoft Visual Studio cannot be used.

How to open FSI file?

The main problem with Visual F# Signature Format is that the FSI file is incorrectly associated with programs. This is manifested by the fact that FSI files open in unusual applications or do not have an assigned program. This can be quickly resolved by following the instructions below.

The first thing you should do is just "doubleclick" on the FSI file icon you want to open. If the operating system has an appropriate application to support it and there is also an association between the file and the program, the file should be opened.

Step 1. Install Microsoft Visual Studio

In this case, you should first verify that the Microsoft Visual Studio application is installed on the computer. The easiest method is to use the system search engine by entering the program name Microsoft Visual Studio in it. If it is not, installation may solve the problem, as most applications create file associations during installation. Later in this article you will find a list of programs that can open FSI files.

Step 2. Create association of Microsoft Visual Studio with FSI files

However, it may happen that the application itself does not cause the FSI file to open in the Microsoft Visual Studio application, but you can set it manually. This option is available from the level of Properties of a specific file available in the context menu. The window will show, among other things, the type of the file and the information by which the program is used to launch the file. Using the "Change" button we can select the desired program. The program should be visible in the window, otherwise it should be selected manually using the "Browse" button and the program installation directory should be indicated. The "always use the selected program ..." field will set the Microsoft Visual Studio application as the default for handling the FSI file.

Step 3. Update Microsoft Visual Studio to the latest version

If, despite the association of the Microsoft Visual Studio program with the Visual F# Signature Format file, the file still does not open, check the program version and possibly update it to the newest version. In this case, use the Microsoft Corporation website or update the program from the application.

Step 4. Check for the following problems with the FSI file

If the above steps do not help, you can assume that the file itself is not correct. File problems can be divided into the following:

The FSI file may be unusually small compared to the original file. This suggests truncating the FSI file contents when downloading or copying. The only repair option is to download the file again.
The computer may have fallen victim to a computer virus or hacker. A virus scan using an up-to-date antivirus program should fix the problem. Some antivirus vendors also provide free online scanners. However, it is important to scan the entire system, not only the file FSI or the program directory. As a result of the scan, sometimes it is not possible to recover FSI files, which are deleted if there is a backup of this file, then after restoring it, it must also be scanned.
A typical compatibility error - the program does not support the older version of the FSI file. These problems are known and are often very easy to fix using the software developers's website.
There can be many reasons for the failure. Depending on the type of file, it is necessary to repair it accordingly. Some programs offer the option of recovering data from damaged FSI files. The easiest way is to restore the file from a backup, if there is one, or contact Microsoft
When reading, a message appears that the file was encrypted or corrupted. The encrypted FSI files cannot be played on other computers than the one on which they were encrypted, they must be decrypted before using on another device.
Some operating systems do not allow file operations in certain locations, eg in system directories or directly on the system drive. While there is usually no problem reading such a file, it may not be possible to save it. Copying the FSI file to another location will fix the problem.
This problem usually affects more complex files. Some file types can only be opened in one program at a time. Running programs (including those in the background) should be verified. If the error persists after closing other programs, wait for a while. Antivirus programs or a backup being made may lock the file for a while without the user's knowledge. If this does not work either, restart the device.