Method 1: Copying the Lonsint.dll File to the Windows System Folder 

1. The file you are going to download is a compressed file with the ".zip" extension. You cannot directly install the ".zip" file. First, you need to extract the dll file from inside it. So, double-click the file with the ".zip" extension that you downloaded and open the file.
2. You will see the file named "Lonsint.dll" in the window that opens up. This is the file we are going to install. Click the file once with the left mouse button. By doing this you will have chosen the file.

   

3. Click the "Extract To" symbol marked in the picture. To extract the dll file, it will want you to choose the desired location. Choose the "Desktop" location and click "OK" to extract the file to the desktop. In order to do this, you need to use the Winrar software. If you do not have this software, you can find and download it through a quick search on the Internet.

   

4. Copy the "Lonsint.dll" file you extracted and paste it into the "C:\Windows\System32" folder.

   

5. If your system is 64 Bit, copy the "Lonsint.dll" file and paste it into "C:\Windows\sysWOW64" folder.

   NOTE! On 64 Bit systems, you must copy the dll file to both the "sysWOW64" and "System32" folders. In other words, both folders need the "Lonsint.dll" file.

   

6. First, we must run the Windows Command Prompt as an administrator.

   NOTE! We ran the Command Prompt on Windows 10. If you are using Windows 8.1, Windows 8, Windows 7, Windows Vista or Windows XP, you can use the same methods to run the Command Prompt as an administrator.

   1. Open the Start Menu and type in "cmd", but don't press Enter. Doing this, you will have run a search of your computer through the Start Menu. In other words, typing in "cmd" we did a search for the Command Prompt.
   2. When you see the "Command Prompt" option among the search results, push the "CTRL" + "SHIFT" + "ENTER
   " keys on your keyboard.
   3. A verification window will pop up asking, "Do you want to run the Command Prompt as with administrative permission?" Approve this action by saying, "Yes".

   

7. Let's copy the command below and paste it in the Command Line that comes up, then let's press Enter. This command deletes the Lonsint.dll file's problematic registry in the Windows Registry Editor (The file that we copied to the System32 folder does not perform any action with the file, it just deletes the registry in the Windows Registry Editor. The file that we pasted into the System32 folder will not be damaged).

   %windir%\System32\regsvr32.exe /u Lonsint.dll

   

8. If you are using a Windows version that has 64 Bit architecture, after running the above command, you need to run the command below. With this command, we will clean the problematic Lonsint.dll registry for 64 Bit (The cleaning process only involves the registries in Regedit. In other words, the dll file you pasted into the SysWoW64 will not be damaged).

   %windir%\SysWoW64\regsvr32.exe /u Lonsint.dll

   

9. We need to make a clean registry for the dll file's registry that we deleted from Regedit (Windows Registry Editor). In order to accomplish this, copy and paste the command below into the Command Line and press Enter key.

   %windir%\System32\regsvr32.exe /i Lonsint.dll

   

10. If you are using a Windows with 64 Bit architecture, after running the previous command, you need to run the command below. By running this command, we will have created a clean registry for the Lonsint.dll file (We deleted the damaged registry with the previous command).

    %windir%\SysWoW64\regsvr32.exe /i Lonsint.dll

    

11. You may see certain error messages when running the commands from the command line. These errors will not prevent the installation of the Lonsint.dll file. In other words, the installation will finish, but it may give some errors because of certain incompatibilities. After restarting your computer, to see if the installation was successful or not, try running the software that was giving the dll error again. If you continue to get the errors when running the software after the installation, you can try the 2nd Method as an alternative.

Method 2: Copying The Lonsint.dll File Into The Software File Folder 

1. In order to install the dll file, you need to find the file folder for the software that was giving you errors such as "Lonsint.dll is missing", "Lonsint.dll not found" or similar error messages. In order to do that, Right-click the software's shortcut and click the Properties item in the right-click menu that appears.

   

2. Click on the Open File Location button that is found in the Properties window that opens up and choose the folder where the application is installed.

   

3. Copy the Lonsint.dll file into the folder we opened.

   

4. The installation is complete. Run the software that is giving you the error. If the error is continuing, you may benefit from trying the 3rd Method as an alternative.

Method 3: Doing a Clean Install of the software That Is Giving the Lonsint.dll Error 

1. Push the "Windows" + "R" keys at the same time to open the Run window. Type the command below into the Run window that opens up and hit Enter. This process will open the "Programs and Features" window.

   appwiz.cpl

   

2. The Programs and Features window will open up. Find the software that is giving you the dll error in this window that lists all the softwares on your computer and "Right-Click > Uninstall" on this software.

   

3. Uninstall the software from your computer by following the steps that come up and restart your computer.

   

4. After restarting your computer, reinstall the software.
5. You can solve the error you are expericing with this method. If the dll error is continuing in spite of the solution methods you are using, the source of the problem is the Windows operating system. In order to solve dll errors in Windows you will need to complete the 4th Method and the 5th Method in the list.

Method 4: Solving the Lonsint.dll error with the Windows System File Checker 

1. First, we must run the Windows Command Prompt as an administrator.

   NOTE! We ran the Command Prompt on Windows 10. If you are using Windows 8.1, Windows 8, Windows 7, Windows Vista or Windows XP, you can use the same methods to run the Command Prompt as an administrator.

   1. Open the Start Menu and type in "cmd", but don't press Enter. Doing this, you will have run a search of your computer through the Start Menu. In other words, typing in "cmd" we did a search for the Command Prompt.
   2. When you see the "Command Prompt" option among the search results, push the "CTRL" + "SHIFT" + "ENTER
   " keys on your keyboard.
   3. A verification window will pop up asking, "Do you want to run the Command Prompt as with administrative permission?" Approve this action by saying, "Yes".

   

2. Paste the command below into the Command Line that opens up and hit the Enter key.

   sfc /scannow

   

3. This process can take some time. You can follow its progress from the screen. Wait for it to finish and after it is finished try to run the software that was giving the dll error again.

Method 5: Fixing the Lonsint.dll Error by Manually Updating Windows 

Most of the time, softwares have been programmed to use the most recent dll files. If your operating system is not updated, these files cannot be provided and dll errors appear. So, we will try to solve the dll errors by updating the operating system.

Since the methods to update Windows versions are different from each other, we found it appropriate to prepare a separate article for each Windows version. You can get our update article that relates to your operating system version by using the links below.

Explanations on Updating Windows Manually 

1. Explanation on Updating Windows 10 Manually
2. Explanation on Updating Windows 8.1 and Windows 8 Manually
3. Explanation on Updating Windows 7 and Windows Vista Manually
4. Explanation on Updating Windows XP Manually