I have been trying for 24 hours to upload app, and first time this has happened in 8 years and 100+ uploads. Please help.
Validate App and Upload both hang indefinitely at "Preparing" in Xcode Organizer. No error is ever returned — the progress bar freezes and the operation never completes or times out. Transporter 1.4.5 fails identically.
Key detail: archive 2.4.3 (build 123), which Apple accepted and processed on Sept 10, 2026, now hangs the same way when validated. Same machine, same Xcode, same Apple ID. This rules out the archive, its signature, and its provisioning profile.
Already ruled out: two independent networks (home Wi-Fi and iPhone cellular hotspot); the archive itself (known-good build 123 fails identically); Xcode install (27.0 / 27A266a, xcode-select verified correct); Apple ID session (signed out and back in three times); full reboot. macOS 27.0 (26A428) on MacBookPro18,4.
Last successful upload Sept 10, 2026. 100+ prior archives uploaded without incident over several years. macOS has updated twice since Sept 10.
Separately: Transporter 1.4.5 crashes on macOS 27.0 with an unhandled exception in TransporterKit while drawing its activity queue (EXC_BREAKPOINT via +[NSApplication _crashOnException:]).
Solved. For anyone who lands here with Xcode 27 Organizer "Validate App" / "Distribute App" stuck forever at "Preparing… Validating…" (Transporter.app too), with no error:
The cause on my Mac was Rosetta. During validation, Xcode's swinfo helper asks for a tool called dwarfdump-classic. Xcode 27 no longer includes it, so macOS falls back to /Library/Developer/CommandLineTools. My Mac had an old Intel-only copy there from 2019 (carried over years ago by Migration Assistant). After a recent macOS update, Rosetta was no longer installed, so that old tool couldn't launch, and swinfo waits forever instead of reporting an error.
What fixed it:
sudo softwareupdate --install-rosetta: validation completed right away. Then I renamed the stale folder (sudo mv /Library/Developer/CommandLineTools /Library/Developer/CommandLineTools-old). Validation still passes: without the old copy, swinfo uses Xcode 27's own dwarfdump.
Quick checks if you're stuck the same way:
Does /Library/Developer/CommandLineTools/usr/bin/dwarfdump-classic exist, and is it Intel-only (file on it says x86_64 only)? Is Rosetta installed? (/Library/Apple/usr/libexec/oah/ should contain libRosettaRuntime.)
What was not the cause, in my case: certificates, network, the archive, Apple ID, or the Xcode license.