Xcode Project won't run on iOS Device

Question

Xcode gives me this message every-time I try running my app on my iPhone. (Works fine on the simulator.) (And this occurs in every project I have.) (I also just downloaded Xcode again.)

This is the message I get.

App Installation Failed.
Unknown Error Occurred.

How do I fix this error?

try restarting your Xcode, and also restart the phone... – almas Jul 09 '15 at 02:07 — almas, Jul 09 '15 at 02:07

score 48 · Answer 1 · answered Feb 01 '16 at 18:47

48

Unplugging iOS Device and plugging it back it in fixed it for me.

answered Feb 01 '16 at 18:47

Oliver S

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i had to make sure that my device wasn't locked while unplugging and plugging it back – kareem Apr 19 '16 at 09:04
Sometimes this is caused by letting the device charging and, when it turns on automatically, I can't use it with Xcode until unplug and plug again. – Dielson Sales Aug 29 '16 at 14:09

score 22 · Accepted Answer · edited May 05 '16 at 18:31

22

Alright, it was a simple fix:

Go into Xcode Preferences -> Accounts -> More Info. Hit the refresh icon.
Clean your project. Project -> Clean.
Force quit Xcode.
Reboot Mac and Device.

edited May 05 '16 at 18:31

Flexo

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answered Jul 09 '15 at 03:32

Amit Kalra

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I started to follow these instructions and was able to fix the issue simply by deleting all my local provisioning profiles and downloading them again. I didn't even need to clean or restart. – atroutt May 16 '16 at 14:14
3

no such thing as 'more info' under preferences -> accounts – Maxi Mus Sep 21 '16 at 14:35
You sir just saved the day. I was stuck on it for two days, then these simple steps worked. Thanks – Hassan Aftab May 03 '17 at 08:51
'simple' fix, eh? – celwell May 26 '19 at 18:31

score 2 · Answer 3 · answered Jul 10 '15 at 06:26

2

If you have the same App but downloaded from AppStore, I suggest to remove the App manually from your device, then try to run the new version with XCode.

answered Jul 10 '15 at 06:26

Lorenzo

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score 1 · Answer 4 · answered Nov 22 '16 at 18:45

After following the suggestions in this thread (restarting iPhone, cleaning Xcode project, quitting and re-launching Xcode) and others (setting Team to None then back to my Team) and unplugging and replugging Lightning connector from my iPhone 6 I was still experiencing this problem. Xcode would even display an error that my iPhone 6 was locked, even though it was not.

I was able to fix it by unplugging the USB-A connector of the USB to Lightning cable from my MacBook Pro, then plugging it back in. I'm not sure why that made the difference, but glad that it did resolve this annoying problem.

score 0 · Answer 5 · answered Dec 12 '16 at 12:37

I have this issue regularly. There are a number of techniques that help me overcome it, including the classic "turn it off and back on again."

One thing that isn't mentioned here is that the iPhone should be switched on, unlocked, connected to the mac and then the app should be run (with the iPhone unlocked). Don't lock it!

score 0 · Answer 6 · answered Oct 11 '19 at 11:09

0

Make sure your device name doesn't have any emoji (Xcode 11.0)

answered Oct 11 '19 at 11:09

ninahadi

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score -1 · Answer 7 · answered Aug 25 '22 at 12:14

-1

if you using vpn services, then you need to turn off vpn. Works for me

answered Aug 25 '22 at 12:14

Artsem Sharubin

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Xcode Project won't run on iOS Device

7 Answers7