Task manager does not always do a very good job at shutting down some applications when they hang/misbehave.
Here are two ways of dealing with it:
The manual way:
1. Open task manager, click ‘View’ then ‘Columns’, then choose ‘PID’
2. In the ‘Applications’ tab, right click on the application that is misbehaving, then click ‘Go to process’.
3. Now it should select the owning process in the ‘Processes’ tab, now take note of the PID (Process ID).
4. Open the command prompt, and issue the command ‘kill <PID>’ (e.g. kill 3437)
The easier way:
1. Install WiXKill from here, it will then sit in your taskbar.
2. Right click on the new task bar icon, and select ‘preferences’ then select ‘kill process’.
2. Now whenever an app hangs and task manager will not kill it, click on the WiXKill utility in your taskbase and just click on the affending application to kill it.