Signing a dmg

I’m tring to sign a dmg file
I’m creating a new configuration file.
When i press on the signing dropdown, i do not see any options.
I have installed certificates in my apple key chain.
What am i doing wrong?

Do you mean that you only see “Unsigned”? If you open the Keychain Access app, which keychain are your certificates in? Do you have any that say “Developer ID Application”?

This what i have on my keychain
In my keychain i have:
3rd Party Mac Developer Application: “my company”
3rd Party Mac Developer Installer: “my company”
Mac Developer: “My name”

Those are Mac App Store certificates. To properly sign for Gatekeeper you need Developer ID certificates. Use the “Developer ID Application” one if you are signing a .dmg or the “Developer ID Installer” one if you are signing a .xip.

Also i have
I also have
Developer ID Application: “My company name”

But still nothing in the drop down

Also
I can see i have this certificate installed under the “Certificates” tab in keychain:
Developer ID Application: “My company”

Which keychain is that in? Does it help if you quit and relaunch DropDMG? Does it show up in the list if you enter this command in Terminal:

security find-identity -v

?

I think i know what the problem
I see the certificate but not as mine since it was made by another team member.
From what i read about this topic, i need to have the certificate private key
I will inform if this resolve the topic
10x!

That’s correct. You need both the certificate its private key in order to sign.