微软社区的解决方案：

1. Left click on windows icon and choose settings.

2. Click on display tab.

3. Change the size of text to 125% Then apply.

4. DO NOT LOG OUT YET. Choose sign out later!

5. Change the text size back to 100% and click apply.

6. Now sign out and sign back in.

Your volume icon will be back. =)

简单来操作就是 右键点击桌面，选择显示设置，上调或下调当前字体显示大小，选择注销(此时一般注销后图标会出现)。

或者稍后注销，再次改变当前字体显示大小，然后应用，注销，音量图标出现。