Fault 1: Double-click the CER certificate. The key string is not installed successfully

When I double-clicked the CER certificate, there was no pop-up for me to enter my password, nor was the certificate found in my keystring. I created a bunch of keystrings, and I’m not sure if this is related, so I just deleted all the keystrings, restarted the keystrings, restarted the computer, and double-clicked to install the certificate.

Fault 2: Double-click the CER certificate. System Roots is displayed

There are two online solutions:

  • Drag the CER certificate into the keychain
  • Delete the entire keystring folder and create a new login keystring

I first tried the first method, dragged it in directly, but didn’t find the certificate. Later, when I deleted other certificates accidentally, it appeared again, which seemed like I didn’t refresh the list, and then deleted a certificate randomly and refreshed it again. The first method failed because deletion was tried later.

I tried to restore the keystring before trying the second method, and the result indicated that I did not have permission.

Then I tried the second method to delete the login key string, but there was still residual data as it was not successfully deleted. Restart the key string, restart the computer to take effect. Then create a new login keystring and double-click install certificate.

Note: if you delete the key string, the account secret and certificate will be cleared

Problem 3: Xcode cannot search for a matching certificate

Double-click here to install the certificate successfully, but strangely it is not installed in my new login keystring, but in the system keystring, and then I move to the login keystring. However, Xcode still indicates that the certificate cannot be found, so it restarts Xcode and finally finds the correct certificate.

Xcode cannot find the certificate installed in the keystring, even after restart. Manage certificate sees revoke displayed on it

This will only happen when < Xcode 11.4.1. Xcode smaller than this will not automatically update the root certificate, which is the root cause of your untrusted installation. Manually download a root certificate and install it. Apple Official Announcement

To summarize the steps:

  1. Double-click to install the CER certificate, if you can prompt to enter the password generally no problem
  2. If “System Roots” error is displayed, try dragging and dropping first, if not successful, try deleting keystring creation (deleting keystring will clear passwords and certificates)
  3. To create a key string, restart the computer and restart the key string
  4. If you do not see the cer certificate after you double-click the certificate and enter the password, check for other keys
  5. Once the certificate is found, you need to restart Xcode so that Xcode will look for the certificate again based on the description file
  6. Check whether the root certificate is expired
  7. If multiple certificates are the same, delete the redundant certificates and retain only one certificate