更新Android Studio2.3後發現以下二個問題：
1.
Gradle sync failed: Unable to tunnel through proxy. Proxy returns “HTTP/1.1 400 Bad Request”
Consult IDE log for more details (Help | Show Log)

2.
Gradle sync failed: Minimum supported Gradle version is 3.3. Current version is 3.2. If using the gradle wrapper, try editing the distributionUrl in C:\yingyou\android\workspase_as\MyApplication\gradle\wrapper\gradle-wrapper.properties to gradle-3.3-all.zip
Consult IDE log for more details (Help | Show Log)

解決：
設定User local gradle distribution

OK。