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缘起：

在配置 Universal Links 的时候，需要在Xcode中配置 Associate Domains，但是配置完，出现下图的错误：

点击 Fix issue，问题依旧，这是为啥？备注：我的xcode版本为 7.3。
莫非是Apple开发者网站上的Associated Domains没有配置？上网站上查看，配置了啊

那咋办？继续找呗，重头到尾检测了遍配置 Universal Links 的步骤，没错，奇了怪了。无奈，求救Google吧，经过各种尝试，发现一个人的评价，顿时有种日了狗了的感觉，原文如下：

pavlibeis
Mar 27, 2016 8:39 AM
(in response to Huang Jobs)
I was fighting 2 days. I had to downgrade to 7.2 to make it work again. I hope this is fixed soon!

3ZS
May 6, 2016 10:58 AM
(in response to Huang Jobs)
This can also be fixed by upgrading to Xcode 7.3.1

于是我果断升级7.3.1（是我自己懒惰，未能及时升级最新版）。结果升级完，还是提示错误，点击 Fix issue后，好用了。oh，shit。苹果啊苹果，真坑啊。一个不经意的bug，害得我找了大半天，那种感觉，你懂的。