Check to make sure you’re connected to the internet. If the device you use with Discord can’t load websites like Discord.com, then fix your internet connection and try to open Discord again.

-Check to see if Discord is down. If the Discord service is offline, you won’t be able to connect to it. This will usually result in your Discord app displaying the update failed message.

-Try a different device. Check to see if Discord works on your phone or another computer. If it does, then you know that there is a specific problem with the device where you are receiving the update failed message.

-Run Discord as administrator. In some cases, granting Discord the extra permissions that come along with running an app as administrator will allow it to punch through any problems, download updates, and open normally.

-Temporarily disable your antivirus. With your antivirus off, check to see if Discord updates and starts normally. If it does, there’s a conflict with your antivirus, and you’ll need to switch to a different one or adjust your antivirus settings to leave Discord alone.

-Rename the Discord update file. If the file is corrupt, this will force Discord to download a new copy and fix the problem on its own.

• Press the Windows key + R.
• Type %localappdata% and press Enter.
• Open the Discord folder.
• Rename Update.exe to UpdateX.exe.
• Try opening Discord, and see if it updates.