Volume icon missing from tool/task bar and can't be enabled

Resolution: 1. "Open up the Task Manager (Ctrl + Shift + Esc) Go to the "Processes" tab, select "explorer.exe" and click "End Process".

2. Click "File" Menu >type "explorer.exe" and hit enter and everything should be back."

3. still does not work,Then select the users tab in the task manager select yourself and click on log off tab at the bottom. Login again and everything should be back."