Windows 10 taskbar icons gone? Here's a simple solution
Windows 10 taskbar icons suddenly gone missing? Quick launch icons disappear and reappear upon reboot? Here's a simple solution that you can try to solve your problem.
Steps
1. Right-click on the taskbar and then click on Task Manager.
Or use the following methods to open Task Manager:
- Right-click on the start menu button and then click on Task Manager.
- Press the [Windows] + [R] keys on your keyboard, type taskmgr and then click on OK or press [Enter].
- Press the [ctrl] + [alt] + [delete] keys on your keyboard and then click on Task Manager.
2. In the Processes tab, you scroll down to Windows Explorer.

Note: If you don't see the Processes tab, then you will have to click on More details located in the bottom left of the Task Manager window.

3. Right-click on Windows Explorer and then click on Restart.

You can also select Windows Explorer and then click on the Restart button at the bottom right of the Task Manager window.

References:
Microsoft Forum: Windows 10 taskbar icons gone? - Answer from VanKnowles
BleepingComputer: Windows 10 quick launch icons disappear upon reboot