Sometimes, you may hover over the system tray and notice missing icons, but there are still blank spaces in their place. This is caused by cached registry settings and can be fixed by following the steps below.
Steps (3 total)
1. Backup Registry
Go to Start > Run (or Windows-key + R), type in regedit and hit OK. Before doing anything else, backup the registry.
2. Navigate to the key:
Delete the values IconStreams and PastIconsStream.
3. Restart Windows Explorer
Open up the Task Manager (Ctrl + Shift + Esc), go to the Processes tab, select explorer.exe and click End Process.
Open the Applications tab and click New Task at the bottom-right of the window.
In the message box that pops up type in explorer.exe and hit OK.
Explorer.exe will reload, and the missing icons should now be back in the system-tray where they belong. Then if the volume bar isn’t there, go to taskbar properties (where the volume was gray) and simply tick the box.
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