Appium Inspector throws an error

I’m running MacOS Sierra v10.12.6, Xcode 8.2.1 and the latest version of the Xcode command line tools, Appium 1.5.3(Ara).
I have a test app, and configured Appium to launch it. When I click the “Launch” button, Appium starts the iOS simulator and launches my app. So far so good.
However, when I click the “i” button to launch the inspector, a “Could Not Launch Appium Inspector” dialog pops up, with this message:
“Could not start a new session
Be sure the Appium server is running with an application opened by using the “App Path” parameter in (along with package and activity for Android) or by connecting with selenium client and supplying this in the desired capabilities object.”

[MJSONWP] Encountered internal error running command: Error: Command failed: ideviceinstaller -u FC72C72B-CC0A-4E31-A494-2C1861ECEBFF -U

at ChildProcess.exithandler (child_process.js:202:12)
at emitTwo (events.js:100:13)
at ChildProcess.emit (events.js:185:7)
at maybeClose (internal/child_process.js:850:16)
at Process.ChildProcess._handle.onexit (internal/child_process.js:215:5)

I hope you’re using latest version of appium client and not the old one.

If you can still reproduce issue with this client then open new issue in github.