Can't submit apps to AppStore: ERROR ITMS-90534: "Invalid Toolchain

Question

ERROR ITMS-90534: \"Invalid Toolchain.

New apps and app updates must be built with the public (GM) versions of Xcode 6 or later, macOS,

Answer 1

Follow this to resolve this issue:

1. Quit Xcode and any Simulators if they are opened.

2. Go to this link to download Xcode 11.2.1 GM seed under Applications. Its about 7GB: https://developer.apple.com/download/

3. After downloading, click the Xcode_11.2.1_GM_Seed.xip file to extract the Archive.

4. After extracting, move the Xcode file from Downloads to the Application folder.

5. Replace existing Xcode application.

6. Enter login password when prompted.

7. Wait for the Moving to complete.

8. When finished, launch Xcode and checkout About Xcode to confirm the latest version.

9. Build your App, increment your build number and submit to App Store.

UPDATE: Version 11.2.1 is now available from App Store itself since Nov 13.