How to Fix Unknown error: Unable to build: the file dx.jar was not loaded from the SDK folder!

Unknown error: to the dx.jar the SDK folder! Recently, I gradually migrated to Android Studio. After updating the Android SDK Manager, I opened the Eclipse Run project and reported an error. Search for various solutions and find:
The version of Android SDK build-Tools has been higher than the version of Android SDK platform-tools, as shown in the figure

Since Android Studio sometimes has to use the higher-version build-Tools, simply deleting the higher-version build-Tools won’t do (see Unknown Error: to the dx.jar the SDK Folder! Solution).
Finally, the relevant answer is found on Stack Overflow (Android ADT Error, was not loaded from the SDK Folder), and the modification is shown in the figure:

Add sdK.buildTools = the build Tools version already installed on your computer

Can.Close test:
Target = android – 24.
SDK buildtools = 25.0.3

You can also avoid this problem by simply deleting the latest 26.0.0 and 27.0.0 folders

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