Install Apps from 3rd party in macOS Sierra

When installed apps from 3rd party or Internet download, macOS always prompt “Downloaded .app is damaged and can’t be opened”.

The solution is really simple:

Run the following command before launching the app:

sudo spctl --master-disable

Launching the app and finish installing it, and then run the following command to re-enable the restriction:

sudo spctl --master-enable

That’s it.

SSH does not work after upgraded macOS sierra?

If you ever met the following errors when trying to git or ssh after upgraded your OS to sierra:

Unable to negotiate with legacyhost: no matching host key type found. Their offer: ssh-dss

Just relax, it’s not your fault but your server’s fault. Upgrading your OS to sierra will also bump your OpenSSH from version 6.9 to 7.2. According to the document of OpenSSH 7 (

OpenSSH 7.0 and greater similarly disable the ssh-dss (DSA) public key algorithm. It too is weak and we recommend against its use. It can be re-enabled using the HostKeyAlgorithms configuration option:

ssh -oHostKeyAlgorithms=+ssh-dss user@legacyhost

or in the ~/.ssh/config file:

    HostKeyAlgorithms +ssh-dss

However, it is probably not enough. You may be prompted for password all the time but no password is correct. In that case, you can simply append another line in your ~/.ssh/config file:

    PubkeyAcceptedKeyTypes +ssh-dss

That’s it! Don’t forget to restart your sshd service before retrying.