Method 1: Installing the Oct2dec.dll Library to the Windows System Directory 

1. The file you downloaded is a compressed file with the extension ".zip". This file cannot be installed. To be able to install it, first you need to extract the dynamic link library from within it. So, first double-click the file with the ".zip" extension and open the file.
2. You will see the library named "Oct2dec.dll" in the window that opens. This is the library you need to install. Click on the dynamic link library with the left button of the mouse. By doing this, you select the library.

   

3. Click on the "Extract To" button, which is marked in the picture. In order to do this, you will need the Winrar program. If you don't have the program, it can be found doing a quick search on the Internet and you can download it (The Winrar program is free).
4. After clicking the "Extract to" button, a window where you can choose the location you want will open. Choose the "Desktop" location in this window and extract the dynamic link library to the desktop by clicking the "Ok" button.

   

5. Copy the "Oct2dec.dll" library you extracted and paste it into the "C:\Windows\System32" directory.

   

6. If your operating system has a 64 Bit architecture, copy the "Oct2dec.dll" library and paste it also into the "C:\Windows\sysWOW64" directory.

   NOTE! On 64 Bit systems, the dynamic link library must be in both the "sysWOW64" directory as well as the "System32" directory. In other words, you must copy the "Oct2dec.dll" library into both directories.

   

7. In order to complete this step, you must run the Command Prompt as administrator. In order to do this, all you have to do is follow the steps below.

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

   1. Open the Start Menu and before clicking anywhere, type "cmd" on your keyboard. This process will enable you to run a search through the Start Menu. We also typed in "cmd" to bring up the Command Prompt.
   2. Right-click the "Command Prompt" search result that comes up and click the Run as administrator" option.

   

8. Paste the command below into the Command Line window that opens and hit the Enter key on your keyboard. This command will delete the Oct2dec.dll library's damaged registry (It will not delete the file you pasted into the System32 directory, but will delete the registry in Regedit. The file you pasted in the System32 directory will not be damaged in any way).

   %windir%\System32\regsvr32.exe /u Oct2dec.dll

   

9. If you have a 64 Bit operating system, after running the command above, you must run the command below. This command will clean the Oct2dec.dll library's damaged registry in 64 Bit as well (The cleaning process will be in the registries in the Registry Editor< only. In other words, the dll file you paste into the SysWoW64 folder will stay as it).

   %windir%\SysWoW64\regsvr32.exe /u Oct2dec.dll

   

10. In order to cleanly recreate the dll library's registry that we deleted, copy the command below and paste it into the Command Line and hit Enter.

    %windir%\System32\regsvr32.exe /i Oct2dec.dll

    

11. If the Windows version you use has 64 Bit architecture, after running the command above, you must run the command below. With this command, you will create a clean registry for the problematic registry of the Oct2dec.dll library that we deleted.

    %windir%\SysWoW64\regsvr32.exe /i Oct2dec.dll

    

12. You may see certain error messages when running the commands from the command line. These errors will not prevent the installation of the Oct2dec.dll library. 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 program that was giving the dll error again. If you continue to get the errors when running the program after the installation, you can try the 2nd Method as an alternative.

Method 2: Copying the Oct2dec.dll Library to the Program Installation Directory 

1. First, you must find the installation directory of the program (the program giving the dll error) you are going to install the dynamic link library to. In order to find this directory, "Right-Click > Properties" on the program's shortcut.

   

2. Open the program installation directory by clicking the Open File Location button in the "Properties" window that comes up.

   

3. Copy the Oct2dec.dll library.
4. Paste the dynamic link library you copied into the program's installation directory that we just opened.

   

5. When the dynamic link library is moved to the program installation directory, it means that the process is completed. Check to see if the issue was fixed by running the program giving the error message again. If you are still receiving the error message, you can complete the 3rd Method as an alternative.

Method 3: Doing a Clean Install of the program That Is Giving the Oct2dec.dll Error 

1. Open the Run tool by pushing the "Windows" + "R" keys found on your keyboard. Type the command below into the "Open" field of the Run window that opens up and press Enter. This command will open the "Programs and Features" tool.

   appwiz.cpl

   

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

   

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

   

4. After restarting your computer, reinstall the program that was giving the error.
5. You may be able to fix the dll error you are experiencing by using this method. If the error messages are continuing despite all these processes, we may have a issue deriving from Windows. To fix dll errors deriving from Windows, you need to complete the 4th Method and the 5th Method in the list.

Method 4: Fixing the Oct2dec.dll Error using the Windows System File Checker (sfc /scannow) 

1. In order to complete this step, you must run the Command Prompt as administrator. In order to do this, all you have to do is follow the steps below.

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

   1. Open the Start Menu and before clicking anywhere, type "cmd" on your keyboard. This process will enable you to run a search through the Start Menu. We also typed in "cmd" to bring up the Command Prompt.
   2. Right-click the "Command Prompt" search result that comes up and click the Run as administrator" option.

   

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 program that was giving the dll error again.

Method 5: Fixing the Oct2dec.dll Errors by Manually Updating Windows 

Some programs need updated dynamic link libraries. When your operating system is not updated, it cannot fulfill this need. In some situations, updating your operating system can solve the dll errors you are experiencing.

In order to check the update status of your operating system and, if available, to install the latest update packs, we need to begin this process manually.

Depending on which Windows version you use, manual update processes are different. Because of this, we have prepared a special article for each Windows version. You can get our articles relating to the manual update of the Windows version you use from the links below.

Guides to Manually Update the Windows Operating System 

1. Guide to Manually Update Windows 10
2. Guide to Manually Update Windows 8.1 and Windows 8
3. Guide to Manually Update Windows 7 and Windows Vista
4. Guide to Manually Update Windows XP