If this error is encountered, you can try to use the Adb or Adbshell command in the root folder where the adb.exe file is located. To do that, open a Command Prompt and navigate to the root folder using the CD command(example
CD C:\Program Files\Android-SDK\ ). To see the available files that are located in a folder use the dir command. When you reached the root folder, try to run the commands again. It should work there.