I update my android studio to 3.2.1
now when I start a new project everything is OK.
but when I open the last project I have an error :
Could not find builder.jar (com.android.tools.build:builder:3.0.1). Searched in the following locations: https://dl.google.com/dl/android/maven2/com/android/tools/build/builder/3.0.1/builder-3.0.1.jar
build.gradle: classpath 'com.android.tools.build:gradle:3.0.1'
My gradle version 4.1
First of all try to invalide caches and restart AS (Android Studio). (File --> Invalide Caches/Restart). If that won't work try to sync project with Gradle Files (File --> Sync project with Gradle files). If it won't work head on to build.gradle(Project: yourappname) and change gradle line in dependencies to the newest version:
dependencies {
classpath 'com.android.tools.build:gradle:3.2.1'
}
hope it will work for you, if not I'll search for other solution