Android Studio 3.0.1错误:Gradle项目同步失败.基本功能(例如，编辑，调试)将无法正常运行

我已经安装了Android Studio 3.0.1，并尝试通过选择一个空活动来构建第一个应用程序，但是我得到了以下消息:

I've installed Android studio 3.0.1 and tried to build very first app with choosing an empty activity, but I've get the message:

Gradle项目同步失败.基本功能(例如编辑，调试)将无法正常工作

Gradle project sync failed. Basic functionality (e.g. editing, debugging) will not work properly

和类似这样的错误消息:

and error message like this:

无法解析':app @ releaseUnitTest/compileClasspath'的依赖关系:无法解析com.android.support:appcompat-v7:26.1.0. 无法解析com.android.support:appcompat-v7:26.1.0. 要求者: 专案:app 无法解析com.android.support:appcompat-v7:26.1.0. 无法解析POM https://dl.google.com/dl/android/maven2/com/android/support/appcompat-v7/26.1.0/appcompat-v7-26.1.0.pom 已经看到的文档类型.

Unable to resolve dependency for ':app@releaseUnitTest/compileClasspath': Could not resolve com.android.support:appcompat-v7:26.1.0. Could not resolve com.android.support:appcompat-v7:26.1.0. Required by: project :app Could not resolve com.android.support:appcompat-v7:26.1.0. Could not parse POM https://dl.google.com/dl/android/maven2/com/android/support/appcompat-v7/26.1.0/appcompat-v7-26.1.0.pom Already seen doctype.

这是日志消息的第一部分:

and this is first part of log message is:

2018-01-03 11:11:12,671 [d线程8]警告-ect.sync.idea.ProjectSetUpTask-已经看到的doctype. 有关更多详细信息，请查阅IDE日志(帮助" |显示日志") 2018-01-03 11:11:12,671 [d线程8]信息-e.project.sync.GradleSyncState-Gradle同步失败:已经看到doctype.

2018-01-03 11:11:12,671 [d thread 8] WARN - ect.sync.idea.ProjectSetUpTask - Already seen doctype. Consult IDE log for more details (Help | Show Log) 2018-01-03 11:11:12,671 [d thread 8] INFO - e.project.sync.GradleSyncState - Gradle sync failed: Already seen doctype.

我尝试了一些建议的解决方案，例如更改gradle版本，更新Kotlin插件(！)等，但是它们没有用.

I've tried some suggested solution like changing gradle version, update Kotlin plugin(!) and so, but they didn't work.

有解决方案吗?