No output device found

Start by updating Windows 10 (version 1909):
Download this -->> MediaCreationTool1909 <<--
Run it
Check --> Upgrade this PC now

Afterwards, if the audio still doesn't work, it may be that the green wire connection is missing in the green jack.

no section for other devices
in audio video and game controllers: Realtek high definition audio
brand: Compaq Presario
Windows 10 64 bit

thank you for your help

In the Reading tab
What do you have in the list?


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Human beings are at their best when things are at their worst.

Hello,

Press Windows + R
Type --> devmgmt.msc and press OK.

Do you have a section --> other devices?

What do you have under audio, video, and game controllers?

What is the brand and exact model number of the PC?

Is Windows 10 32 or 64 bits?

--
Human beings are at their best when things are at their worst.

Press Windows + R
Type --> control panel and OK.

Go to Sound
In the Playback tab, do you have Realtek High Definition Audio (speakers) set as default?
Example image:


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Human beings are at their best when things are at their worst

I've got a red arrow pointing down and it says not connected.

I recovered this computer..
version 1903

Have you connected the green wire for the speakers?
Behind the PC, is the green wire properly plugged into the green jack on the PC?

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Human beings are at their best when things are at their worst.

what speakers

Press Windows + R
Type --> devmgmt.msc and OK.

Go to Sound, video and game controllers
Right-click on --> Realtek High Definition Audio
Uninstall
Check: delete the driver ....
Uninstall

Windows + R
Type --> control panel and OK

Programs and Features
Uninstall --> Realtek High Definition Audio, if present
Restart the pc.

Download and install this driver --> Realtek

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Human beings are at their best when things are at their worst.

It's fine.
The sound icon at the bottom still has a red cross, but a new icon has appeared.
Should I do anything else?

a new icon has appeared

What is the icon?

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Human beings are at their best when things are at their worst

an orange sound icon "Realtek HD Audio Manager"

otherwise after an attempt it still doesn't work