If you are trying to launch an app on OS X and simply get the error “The application XXX can’t be opened”, the problem could be the actual executable file in the app bundle does not have corresponding permissions.
To fix the issue:
- Open a Terminal and enter into your app bundle. You can just type “cd ”
and then drag the app into the Terminal and then hit the enter.
- cd Contents/MacOS
- chmod +x * or chmod +x <FILENAME> if you know which one is the actual executable.
- sudo !! may be needed if you don’t have permissions to execute step 3.
Now try to launch the app again, and the problem should be solved.
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
To restart ssh/sshd service in Mac OS X, you can simply run the following two commands together:
sudo launchctl stop com.openssh.sshd
sudo launchctl start com.openssh.sshd
Your sshd will get restarted and your new ssh config file can be loaded as well.
p.s. Friendly reminding: DO NOT try to execute
sudo launchctl reboot com.openssh.sshd
instead since your computer will immediately get rebooted 🙂
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 (http://www.openssh.com/legacy.html):
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:
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:
That’s it! Don’t forget to restart your sshd service before retrying.
After you have upgraded your OS X into Yosemite, the following dialog would appear when you are trying to launch Adobe Creative Suite:
You can click “More Info…” button to open safari to download Java for OS X 2014-001. That can solve the problem.
Sometimes, you would see a blank page instead, totally blank, whose url is: http://support.apple.com/kb/DL1572
Don’t worry, you can simply click the following link to download Java for OS X 2014-001 directly:
I don’t know why, but sometimes it really happens.
When you upgrade your OS X to 10.10 Yosemite, you may find some icons in the Dock are missing.
There is a simple solution for this:
For each missing icon, right click the icon then choose Options -> Show In Finder. Aha, the icons come out!
例如：Ctrl-F(Forward) 相当于 PageDown，Ctrl-B(Backward)相当于PageUp。
再比如：^ 相当于Home，$ 相当于End（意义来自正则表达式）。