iOS 10.3无法安装企业In-House APP问题 ，在 stackoverflow 上有： https://stackoverflow/questions/43060212/cant-download-ios-app-using-in-house-at-ios-10-3-release-version

Can't download iOS app using in house at iOS 10.3 release version

具体解决方案就是：
I figured it out, it seems just trusting the certificate is no longer enough. You need to go into General -> About (yes, About, what a great place) -> Certificate Trust Settings. Then tick the switch next to your CA to trust it.


10.3开始，需要事先信任一下下载的CA证书，否则无法下载APP。