对于那些仍然在Xcode8中与这个问题作斗争的人。对于我来说，这是一个重复的证书问题，这是我解决它的方法:

我读了尼克的回答，然后开始了我的调查。我检查了我的特定案例中的所有密钥和证书(在~/Library/Keychains/System.keychain中)。

When I opened the file, I found that I had two iPhone Distribution Certificates (that was the certificate that Xcode was requesting me), one with the iOS Distribution private key that I have been using since the beginning, and another iPhone Distribution Certificate which its private Key had a name (iOS Distribution:NAME) that wasn´t familiar for me. I deleted this last certificate, started Xcode again and the problem was gone. xCode wasn´t able to resolve that conflict and that´s why it was giving signing certificate error all the time.

检查你的钥匙链，也许你有一个重复的证书。

您还可以使用Fastlane工具包解决代码签名问题。作者投入了大量精力来有效地自动化构建、签名iOS应用程序(等等)。

因此，在上述套件中，有一个工具sigh，它神奇地解决了任何签名问题，因此得名:)这里的好处是，这个工具封装了关于常见签名问题的知识，可以检测和解决大多数问题。

Fastlane安装为Ruby gem:

Gem安装fastlane

然后简单地引用:

快速的叹息——发展

回答两个问题，瞧:

[11:56:55]: No existing profiles found, that match the certificates you have installed locally! Creating a new provisioning profile for you
[11:57:01]: Creating new provisioning profile for 'com.myapp' with name 'com.myapp Development'
[11:57:06]: Downloading provisioning profile...
[11:57:09]: Successfully downloaded provisioning profile...
[11:57:09]: Installing provisioning profile...

最后，进入Build Settings -> Signing，切换到新创建的配置文件，其名称您刚刚在命令回显中看到。

此示例用于开发代码签名问题(在设备上运行)。查看所有其他选项的叹息文档。

Delete the developer certificate that does not have a private key. Delete the provisioning profile from your machine using go to folder (~/Library/MobileDevice/Provisioning Profiles) Then first check then uncheck the Automatically manage signing option in the project settings with selecting team. Sing in Apple developer account and edit the provisioning profile selecting all available developer certificates then download and add to XCODE. Select the provisioning profile and code signing identity in project build settings

检查您的钥匙串，查找缺少私钥的身份。我为同一个团队安装了多个分发证书，其中一个缺少私钥。Xcode只检查密钥链中第一个匹配的标识，并自动使用这个标识，而不是包含私钥的标识。

删除没有私钥的匹配标识使Xcode再次检测到正确的标识。

如果您尝试将应用程序上传到iTunes Connect(您的供应配置文件设置为分发)，请转到项目设置->构建设置->代码签名。请确保将所有调试和发布选项设置为您的分发配置文件。

Xcode 11

这是我得到的错误

配置文件“XXX”不包含签名证书“Apple Development: XXX (XXX)”。

现在Xcode 11自动创建了一个证书“Apple Development: XXX”，该证书对所有平台都有效

你只需要

访问https://developer.apple.com 转到配置配置文件 检查是否已选择此证书