Android studio after updates does not see connected devices

Question

After updates to Android Studio 3.6.1 studio does not see connected devices,
but in adb devices

the debugger also stopped working
also do not work:

adb kill-server
adb start-server

I tried using the emulator, but the debugger in it also does not work

Operating System: MacOS Mojave

Answer 1

Decision:
Studio changed the way to platform-tools it used to be:

/Library/Android/sdk/platform-tools

after the update:

/Library/Android/sdk/platform-tools/platform-tools

I don’t know why this happened, but after I moved all the content from the nested platform-tools, everything worked

Answer 2

First try

To change what your application defaults to when you click run or debug in Android Studio, follow these steps:

1. go to Run

2. Click on Edit Configurations

3. Select the project

4. find the Target Device section under the General tab on the Android Application page.

That seems to be where you toggle what the project builds to. If you're importing a project it actually defaults to Emulator, not sure why. You can also select "Open Select Deployment Target Dialog" to list both connected as well as emulated devices.

Sec try

Go to device manager (just search it using Start) and look for any devices showing an error. Many androids will show as an unknown USB device and comes with exclamation mark. Select that device and try to update the drivers for it. for update part follow the link:universal adb

But before that, you have to update your sdk manager and make sure Google USB Driver package is installed.

When done, the driver files are downloaded into the \extras\google\usb_driver\ directory. Hints: Search "android_winusb.inf" under Windows Start and Open File Location to get the directory mentioned.

Open up your device manager, navigate to your android device, right click on it and select Update Driver Software then select Browse driver software. Follow the file location path previously to install Google USB Driver.

Third try

Some cables can not been used for developer mode or transfer file. A solution would be change your cable and don't waste time.

and be sure allow USB debug mode

fourth try

Drivers not installed: If the Android Physical device is not a Google/Nexus product than you have to download the OEM drivers of the particular model.

HAXM not installed properly : Hardware Accelerated Execution Manager must have not installed properly on your computer. Try reinstalling it directly from the options available in your SDK.

No proper Path : Sometimes though the files are available in the local system, The Android Studio is not guided with the accurate path name to reach the file.

............... Before going to bellow steps make sure

Your "Google USB Driver" package is installed ("Tools" -> "SDK Manager" -> Check "Google USB Driver" -> "Apply" -> "Ok").

If you are trying to access with emulator then check "Intel x86 Emulator Accelarator(HAXM installer)" is instaled. ("Tools" -> "SDK Manager" -> Check "Intel x86 Emulator Accelarator(HAXM installer)"" -> "Apply" -> "Ok")

Go to Tools. Then go to SDK Manager. Open SDK tools. Uncheck "Android SDK Platform-Tools" (On my case it was checked). press apply then ok. Again goto Tools. Then goto SDK Manager. Open SDK tools. check "Android SDK Platform-Tools" Restart Android Studio :)

Hope this will be useful to you.