[ios] How can I add private key to the distribution certificate?

Well, I've got my Developer Certificate linked with it's private key. Works Fine.

I've downloaded my iOS Profile of distributor, but it says Valid signing identity not found.

So I checked my certificates, and exactly, my developer certificate it's linked with its private key but not my distribution certificate. How can I link/add my private keys to this certificate!?

Will this solve the problem "Valid Signing identity not found"?

Since the existing answers were written, Xcode's interface has been updated and they're no longer correct (notably the Click on Window, Organiser // Expand the Teams section step). Now the instructions for importing an existing certificate are as follows:

To export selected certificates

1. Choose Xcode > Preferences.
2. Click Accounts at the top of the window.
3. Select the team you want to view, and click View Details.
4. Control-click the certificate you want to export in the Signing Identities table and choose Export from the pop-up menu.

5. Enter a filename in the Save As field and a password in both the Password and Verify fields. The file is encrypted and password protected.
6. Click Save. The file is saved to the location you specified with a .p12 extension.

Source (Apple's documentation)

To import it, I found that Xcode's let-me-help-you menu didn't recognise the .p12 file. Instead, I simply imported it manually into Keychain, then Xcode built and archived without complaining.

What i did is that , i created a new certificate for distribution form my Mac computer and gave signing identity from this Mac computer as well, and thats it

This site explain step by step that what you need to do Certificates, Identifiers & Profiles and as your question

"Valid Signing identity not found"?

You need the private key that were used to sign the code base with provisioning profile. . If you don't have then you can generate a new signing request on the iOS developer portal.

For Export:

Xcode -> Organizer, select your team. Click Export. Specify a filename and a password, and click Save.`

For Import:

Xcode -> Organizer, select your team. Click Import. Select the file containing your code signing assets. Enter the password for the file, and click Open.

With Xcode 9 the interface has been updated and now the way I did to resolve the problem was this:

1. Choose Xcode > Preferences.
2. Click Accounts at the top of the window.
3. Select the team you want to view
4. Click the gear icon () in the lower-left.

5. Export Apple Id and Code Signing Assets
6. After entering a filename in the Save As field and a password in both the Password and Verify fields you'll see a Window like this

7. Click the gear icon () -> Click Import -> Select the file you exported in step 6

"Valid Signing identity not found" This is because you don't have the private key for distribution certificate.

If the distribution certificate was created originally on a different Mac you may need to import this private key from that Mac. This private key is not available to download from your provisioning portal.

When you import the correct private key to your mac , XCode's organizer will recognize your already downloaded distribution profile as a "Valid profile"

However if you do not have access to the original Mac which created those profiles, the only option you have is revoking profiles.

For Developer certificate, you need to create a developer .mobileprovision profile and install add it to your XCode. In case you want to distribute the app using an adhoc distribution profile you will require AdHoc Distribution certificate and private key installed in your keychain.

If you have not created the cert, here are steps to create it. Incase it has already been created by someone in your team, ask him to share the cert and private key. If that someone is no longer in your team then you can revoke the cert from developer account and create new.

since xcode5 organizer no longer team section exists. but the bold sentence was the answer for me. God thanks there is another mac to restore and import to problemmatic mac. now all is ok.