Unfortunately, it can happen that a program or application suddenly stops responding to commands, forcing you to force it to close. There are several ways to do this, depending on the severity of the problem and the operating system you are using.
Steps
Method 1 of 3: Using the Task Manager (Windows Systems)
Step 1. Press the hotkey combination Ctrl + Alt + Del
This will display a contextual menu consisting of 4 options on the screen: Block, Change user, Disconnect And Task Manager or Activity management (depending on the version of Windows you are using).
Step 2. Choose the Task Manager item or Activity management.
This Windows feature provides information about the processes, programs, and services currently running on the system.
Step 3. Select the Task Manager window
If after selecting the item Task Manager you do not see any system window appear on the screen, it could be hidden by that of the blocked program. Try using the key combination Alt + Tab ↹ to view all open windows and be able to select the Task Manager window.
Prevent this problem from recurring in the future by accessing the "Options" menu of the Task Manager and selecting the check button Always on top.
Step 4. Locate and select the blocked program
It will most likely be listed within the section Applications. When a program stops working correctly or no longer responds to commands, inside the column State you will find the wording Not responding.
Step 5. Press the "End Task" button
After selecting the program under consideration so that its name is highlighted in blue, press the button End activity located in the lower right corner of the window. At this point, when prompted, press the button End program located inside the pop-up window that appeared.
Troubleshooting
Step 1. Go to the "Processes" tab
If the previous method did not have the desired effect, you will have to terminate the process related to the program in question. If you are using Windows 8, to have access to the card Processes you will have to press the button More details located at the bottom of the "Task Manager" window.
Step 2. Identify the process of your interest and select it
The "Processes" tab lists many more items than the "Applications" tab, as all programs running in the background are also included. Identifying the process related to the program to close may not be immediate.
Step 3. Press the "End Task" button
Once you have located and selected the correct process, press the button End activity located in the lower right corner of the "Task Manager" or "Task Manager" window.
Method 2 of 3: Use Command Prompt (Windows Systems)
Step 1. Open a Command Prompt window as a system administrator
Press the ⊞ Win key on your keyboard, then type the command cmd. Select the icon of Command Prompt appeared in the search results list with the right mouse button, then choose the option Run as administrator from the context menu.
If prompted, press the button Yup located in the "User Account Control" window that appears on the screen.
Step 2. Close the program in question
Type the string taskkill / im [filename].exe within the Command Prompt window, then press the Enter key. Replace the parameter [filename] with the name of the program you wish to terminate. For example, if you are trying to shut down iTunes, you will need to use the command taskkill / im iTunes.exe.
Method 3 of 3: Using the Force Quit Feature (Mac)
Step 1. Open the "Force Quit" window
To do this, press the key combination "Command + Option + Esc". Inside you will find the complete list of all currently active programs.
Step 2. Force close the desired program
Find the blocked application, select it with the mouse, then press the button Forced exit located in the lower right part of the window.
