Xcode error: Failed to prepare device for development

I have updated to Xcode 12.3 beta. device version is 14.2, but Xcode complaining:

> Errors were encountered while preparing your device for development. Please check the Devices and Simulators Window. > > Failed to prepare device for development

iPhone directly connected to MacBook. I have tried all mumbo jumbos on the web. but no success any idea?

> Unable to prepare DEVICE for development > > Please check the connection to the device, and review all errors in the Devices and Simulators window.

A simple phone restart will fix it

I have had to come back to this SO question twice in the past couple weeks. First time, I did have to update my Xcode and iOS versions, which fixed the issue. Now, the issue has returned, but there are no updates. I tried disconnecting and reconnecting my phone from my laptop, but to no avail.

What fixed it the second time was merely restarting my phone. I am curious if that would have fixed it the first time too, without needing to have updated.

I know this is just echoing the other answers here, but at the very least, I would recommend just starting with a simple phone restart and seeing if that fixes your problem. Here is the specific screenshot that I encountered, in case yours is the same (pro tip: you can open up the "Devices and Simulators" window by going to Window -> Devices and Simulators shift-command-2).

Exact same problem here, this solved the issue for me:

• Delete the app from the phone
• Clean the Build Folder with: ⌘ + shift + K
• Delete derived data
• Unpair device (from ⌘ + shift + 2 window)
• Disconnect iPhone
• Restart iPhone
• Restart Mac
• Trust

After this, it worked for me.

This error shows because of iPhone OS version is not supported by Xcode that's why this warning popped up, so check which max ios version is supported by Xcode which you are using.

In my case, the Xcode version is 13.1 and my iOS version is 15.4 so what I did, First downloaded device support version 15.4 from here (Download according to your device version) and added this to my Xcode.

steps to add the file in Xcode:-

1. Go to Applications > Right click on Xcode and Select Show Package Contents > Contents > Developer > Platforms > iPhoneOS.platform > DeviceSupport.

2. Extract your device support file to DeviceSupport Folder.

3. Restart Xcode and unplug and plug in your device.

I restarted my iPhone(14.2); now both Xcode 12.3 beta and 12.2 can run app on my device.

I could not get the phone to authorize until I had the paired Apple Watch trust the computer as well. A more helpful error message could be imagined.

Both the iPhone and the paired Apple Watch must trust the computer before the phone can be successfully prepared for development.

In my case was to keep the iOS version with my Xcode version in sync.

Xcode 12.3 with iOS 14.3

Thanks Matt for hint: Updating device iOS to 12.3 beta fixed the problem.

if you updated you iOS to latest beta version, you should also use latest Xcode beta version.

What worked for me was to go to Xcode Devices and Simulators window, then ...

• right click on the Connected device, and select "Show Provisioning Profiles" menu item, then delete all the provisioning profiles,
• right click on the Connected device, and select "Unpair Device" menu item
• Unplug and reboot the phone

I tried most suggestions here. The only thing that ended up working was unpairing my phone in Xcode then unpairing my apple watch from my iPhone. Connects just fine now. iOS (14.3) Xcode (12.3)

Exact the same problem with Xcode 12.3 beta ; for me, just have to: Disconnect the phone Restart the phone still on ios14.2

-> data cable off

-> data cable on

and it works :)

Solution: Update your Xcode to a newer release date than your iOS Release Date.

I experienced this problem when using the iPhone's personal hotspot on my Mac. The fix was to disconnect the phone from the computer, then disconnect from the personal hotspot and reconnect again. Apparently this makes the mac use the wifi hotspot (and not the usb hotspot on the iPhone, which messes things up when debugging).

As many people mentioned/suggested, restarting my iPhone solved the problem.

My setups are: Catalina 10.15.7, Android Studio 4.0, Flutter 2.01,and Xcode 12.4.

I think having an apple watch paired to your iphone causes some issues.

I had trusted from my apple watch, but was still having this issue. Unparing my apple watch from my iphone was the only thing that worked for me:

• unpair apple watch from iphone
• unpair iphone from xcode

Restart both, and don't pair apple watch until the iphone is paired.

and, if you have any other problems, and are using flutter, run flutter doctor, and ensure you have cocoapods installed.

and once again, if Flutter issues, follow the details here to ensure you have your signing setup correctly

also, if things aren't working, then do a flutter clean, and then try again.

I just solved my issue removing the iPhone cable and putting it back.

This solved the issue for me:

• Delete the app from the phone
• Clean the Build Folder with: ⌘ + shift + K
• Unpair device ⌘ + shift + 2
• Disconnect iPhone

Updating Xcode is a fix because old versions of Xcode can't talk to new versions of iOS (see https://developer.apple.com/support/xcode/ for compatibility).

If you're stuck on an old version of Xcode you can use something like https://github.com/iGhibli/iOS-DeviceSupport or https://github.com/filsv/iPhoneOSDeviceSupport which installs the newer device support files into older versions of Xcode.

Nothing from the above listed helped me and also I have encountered this problem when the app was removed for a while. But turning off the phone for 10 mins solved the problem.

My Current Setting and Versions: XCode 12.4 and iOS 14.4

• I had to update XCode since my iOS was updated. This fixed the compiler error in Unity and then the same message popped up during deployment. All I did was disconnect/re-connect.

Restarting the iPad works for me every time!

I just had to unpair the phone from Xcode's Devices and Simulators screen and then tap Trust when connecting it to the computer to make my Watch work with Xcode

1. cmd + shift + 2
2. Click the red cross to check error detail
3. In most cases, the error message shows your xcode supported iOS version is lower than your iPhone's iOS version.
4. Update your xcode.

In my case, after updating iPhone to a newer iOS version then got this issue.

The solution is needed to update XCode to the latest version and everything is ok.

I had to change the iOs Deployment target to "iOs 15". Then it worked. After that, I just set it back to iOS 12, and everything keeps working.

If nothing worked for you, try the below steps.

• Update the Xcode
• Update the iOS version
• Connect mac and iPhone to the same wifi

just Clean the Build Folder with: ⌘ + shift + K

I got it resolved today by upgrading OS on my Mac to 12.3.1 and Xcode to 13.3.1 as well as restarting and re-connecting devices couple of times.

In my case solution was:

• General settings on phone device
• Profiles & Device Management
• Open developer app and click on Trust

I got the same error message after updating Xcode to 12.4. I have disconnected and reconnected iPad. Then, I have waited for 1 or 2 minutes for Xcode to process device's cache files. Finally, I could run my application in device.

For me, it was a "Trust" issue, where in the past, after the long build process, finally XCode would try to install on the phone, and by then it would have forgotten that I selected to "trust" the mac (on the phone), and give some error message that I needed to disconnect and reconnect the phone to run the app on it. This was with earlier versions of Xcode.

This time, with Xcode 12.3, that error message didn't show up, but instead, got this unhelpful generic error message. I had selected to trust the Mac earlier, but I think because of the long build process, and the machine went to sleep during that time, then the Mac "forgot" that I had chosen to trust it. The next time, I disconnected and reconnected the phone, selected "trust" again, and babysat the phone to stay awake while the re-build was happening. Then it worked.

I didn't have to reboot the phone or mac or even restart Xcode.

I found that if the device is in "Low Power Mode" it would result in this error. So just deactivate it in your settings.

Running Xcode 12.4 and iOS 14.4 on an iPhone Xs and ran into same issue today. First time I've seen it. I wanted to echo what many of the other contributors here have already indicated; rebooting the iOS device did the trick.

We encountered this error and determined it was due to a damaged iPhone cable. New cable, problem solved.

The steps below, work for me :D

• Delete the app from the phone
• Clean the Build Folder with: ⌘ + shift + K
• Delete derived data
• Unpair device (from ⌘ + shift + 2 window)
• Disconnect iPhone
• Restart iPhone
• Restart Mac
• Trust

Thanks !!!

Me help is set mark radio "connect via network" (on the top right devices and simulators menu)

I faced the same on my iPhone running iOS 15.0 while trying to run my app from Xcode 13.0, killing the UBS demon helped me, no restart was required.

sudo killall -STOP -c usbd 

More from Apple Developer Forum.

I had the same issue and tried all the other suggested fixes:

• Cleared Derived Data
• Xcode clean/restart
• Removed paired device
• Restart device
• Restart Mac
• Trust the computer on both Device and Apple Watch again

In the end the only thing that worked for me was to update my paired Apple Watch Series 3 to the latest OS version.

After Mac and iPhone rebooting, if you have Apple Watch - wear them and input trust code or even reboot them.

What helped me after phone restart is, on the phone:

1. Go to settings
2. Developer
3. Forget trusted devices (its the first button)
4. Reconnect the phone to the mac
5. Click trust on the phone
6. Exit settings(otherwise it will say that your phone is busy)
7. Click that play button in XCode