When the sound icon in the task bar has a red x on it, you definitely cannot hear the sound. You move the cursor over the sound icon and it shows “No Audio Output Device is installed”. When you encounter this sound error, you can try solutions here then the problem should resolve.
To fix the problem, follow these steps (Steps below are for your reference. The specific steps in different system versions may be different. ):
1. Press Win+R (Windows key and R key) at the same time. A Run dialog will appear.
2. Type devmgmt.msc in the run box and click on OK button.
3. Find category “Sound, video and game controllers” from the list. If you do not see this category listed there, follow steps below to get it back.
1). Select ‘Action‘ from menu bar (If you only see ‘Help’ under this option, please click the blank place of the list pane then click ‘Action’ again. )
2). Select ‘Add Legacy hardware‘
3). Add Hardware Wizard will come up. Click Next button. (If Add Hardware windows doesn’t appear, try the Final Solution.)
4). Select ‘Search for and install hardware automatically
5). If message that the wizard did not find any new hardware comes up, click Next.
6).You should now see a menu of hardware types.
Scroll down until you see the Sound, video and game controllers option.
7). Highlight that option then select Next.
8). Select the manufacturer and model of the sound card and then click Next. For instance, if you are using Realtek audio card, select Realtek. (If you are not sure what manufacturer you should select, try the Final Solution.)
9). Click Next to install the device and click Finish.
4. Under this category, right-click on the audio device. Click Enable in the pop up menu. (If the device is already enabled, disregard this step.)
5. If this does not resolve the problem, click Uninstall to uninstall the driver.
6. Restart your PC. After restarting, the system always can automatically load the sound driver, then the problem should resolve.
The problem most probably is caused by driver issues. If you are not sure how to follow steps above to resolve the problem manually, you can use a driver update tool to help update drivers automatically. Driver Easy is one of driver update tools online. After you install Driver Easy, use it to scan your computer to detect all problem drivers. If there is problem with the audio driver, Driver Easy will detect it and recommend the new driver. With Driver Easy, the sound issue can be resolved easily.
Driver Easy has Free version and Paid version. You can use the Free version to download new drivers, but you are required to use the downloaded driver files to install the drivers manually step by step. And the download speed is limited. To save more time, you can use the Paid version. With Paid version, all drivers will be updated automatically. More over, you can enjoy free technical support guarantee. If you use the Paid version to try resolving the problem but the problem persists, you can contact us for further assistance. Paid version offers 30-day money back guarantee. You can ask for a full refund if you want within the guarantee period.