Solve the problem of adb no devices/emulators found

created at 08-17-2021 views: 146

Recently, I have always encountered the problem of adb disconnected from time to time, and then connected to adb no devices/emulators found.

Many claims on the Internet are basically nonsense.

  • Change the line: some lines can only be charged
  • Change the USB expansion port: the power supply of the inferior expansion port is unstable.
  • Restart the phone/computer, unplug and plug a few more times, even flash the phone, unlock bootloader: The reason why it works occasionally is the same, that is to let you unplug and retry multiple times. After a few more attempts, you will have a chance to successfully seize the device access.

If you have been using the same cable, the same device, and the same usb port, but it will not work for a while, it is 80% that you have encountered my situation, so you can continue to look down.

Under Mac, we can see the system log through the Console (console), pay attention to a paragraph of content when the phone is just plugged in:


It can be seen from the log output that Android File Transfer also cannot connect to IN2020 (my OnePlus Pro 8 model):

241378.161008 Android File Tra@(null): AppleUSBHostUserClient::openGated: could not open provider IN2020. provider already opened for exclusive access by Google Chrome

The reason is that the provider IN2020 (I don't know which domain concept...) has been opened by Google Chrome in an exclusive (exclusive, unique) access mode. The same is true for adb not being able to connect.

After investigation, I can use adb normally after I close the Chrome inspect page. Turning off "Discover USB devices" in the inspect can also solve this problem. According to my needs, I don’t need this feature for the time being, so I can turn it off even if the inspect is turned on. The problem does not occur:

Discover USB devices


created at:08-17-2021
edited at: 08-17-2021: