The problem: When you try to launch any 16bit application on Windows 10 (32bit), you get the following error: "16 bit MS-DOS Subsystem. <Program's name>. NTVDM has encountered a System Error. The handle is invalid. Choose 'Close' to terminate the application."
This tutorial contains instructions to resolve the "NTVDM has encountered a System Error" issue when open 16-bit applications on Windows 10.
How to fix NTVDM encountered a System Error in Windows 7 & Windows 10. *
* Notes:
1. If you face the NTVDM error in Windows 7, try to change the compatibility mode of the DOS program to "Windows 98/Windows ME" and if the problem persists apply the instructions in Step 3.
2. If you face the NTVDM error in Windows XP, change the compatibility mode of the DOS program to "Windows 98/Windows ME" and if the problem persists apply the instructions uninstall the Updates KB2707511 and KB2709162.
Step 1. Enable NTVDM Component.
1. Simultaneously press the Win 
+ R keys to open the run command box.
2. Type the following command and press OK.
- control panel
3. Change the View by to Small icons on the top right to view all control panel items.
4. Open Programs and Features and then click Turn Windows Features on or off from the left.
5. Expand Legacy Components, check the NTVDM option and click OK.
Step 2. Enable Legacy console.
1. Simultaneously press the Win + R keys to open the run command box.
2. Type cmd to open command prompt.
3. Right-click at the Command Prompt top bar (next to title) and choose Properties.
4. Check the "Use Legacy console (requires relaunch)" option and click OK.
5. Close Command Prompt and launch your MS-DOS application. The NTVDM problem must be resolved until now.
* Note: If you still receive the NTVDM error when running 16 bit applications then proceed to the next step.
Step 3 (Optional *). Enable Access to 16-bit Applications from Registry or Group Policy.
* Notice: The instructions at this step are optional. Apply them only if you still have problems when running 16-bit programs on Windows 10 (or in Windows 7 OS).
Windows 7 & 10 Home or Pro.
– To enable access to 16-bit applications on Windows 10 Home:
1. Simultaneously press the Win + R keys to open the run command box.
2. Type regedit and press Enter to open Registry Editor.
3. Navigate to this key from the left:
- HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows
4. Right click on Windows and choose New > Key.
5. Name the new key "AppCompat" (without quotes) and press Enter.
6. Highlight the AppCompat key and then right click at the right pane and choose New > DWORD (32-bit) Value.
7. Name the new value "VDMDisallowed" (without quotes) and press Enter..
8. Double click at the VDMDisallowed value and type 0 in the data box.
7. Click OK when done and close Registry Editor.
8. Restart your computer.
Windows 7 & 10 Pro.
– To enable access to 16-bit applications on Windows 10 Pro.
1. Simultaneously press the Win + R keys to open the run command box.
2. Type gpedit.msc and press Enter to open the Local Group Policy Editor.
3. In Group Policy Editor navigate (from the left side) to:
- Computer Configuration > Administrative Templates > Windows Components > Application Compatibility.
4. Double click to open the Prevent access to 16-bit applications (at the right pane).
5. Click Disabled, click OK and close Group Policy Editor.
That's it! Let me know if this guide has helped you by leaving your comment about your experience. Please like and share this guide to help others.