Win7 computer speakers have no sound how to do

First of all, we do not plug in the headset, in the case of computer hardware equipment working properly, see what kind of prompts the system will give.
Open the Start Menu--Control Panel to find and fix problems in System and Security.

Turn on hardware and sound, under Sound Options, select Play Audio; in the Play Audio dialog box, click Next.

In the fault dialog, select Headphones and click Next. The computer should prompt: the peripherals are not plugged in and give suggestions for repair: plug in the speakers or headphones.

At this point we can plug in the headset and click Next. The system will automatically change the repair and give the following dialog box:

If we did not plug in the headset in the previous step, and directly click Next, the prompt message will be as follows:

So, we Simply select the option to be checked and the system will automatically help with the check and give the appropriate fix suggestions.