While changing the Mirror in Software Sources I am getting this error. I am posting screen shot of error. Please note I am not a techie. Thanks in advance.
Was it OK before that change?
What did you exactly change?
Does it “heal” if you revert the change?
If this MS repo was newly added, you’ll have to get the public key of the repo owner/signer and add it to your packaging system (apt?).
In general, keep your fingers away from unsigned repos!
EDIT: Your URL looks wrong; where does it come from?
I installed VS Code using a DEB I download from Microsoft. It added a file to /etc/apt/sources.list.d/ named vscode.sources. It must have also added a gpg key.
$ cat /etc/apt/sources.list.d/vscode.sources
### THIS FILE IS AUTOMATICALLY CONFIGURED ###
# You may comment out this entry, but any other modifications may be lost.
Types: deb
URIs: https://packages.microsoft.com/repos/code
Suites: stable
Components: main
Architectures: amd64,arm64,armhf
Signed-By: /usr/share/keyrings/microsoft.gpg