AIR 51.3.2.2 iOS app crashes with “Packaging Error, assets.car file”

ElOil1975

Hi everyone,

I am currently having a critical issue with iOS packaging using Adobe AIR SDK 51.3.2.2 and would like to know if this is a known regression or if anyone has found a working solution.

Environment:

Adobe AIR SDK: 51.3.2.2
Adobe Animate
Xcode 26
iOS 18 / iPadOS 18+
Pure AIR application (NO ANEs, NO distriqt extensions)

Problem:
If I package my app using a custom Assets.car, the app installs successfully on the iPad/iPhone, shows the splash/title screen for about one second, then immediately crashes with the message:

“Packaging Error, please check your assets.car file”

What I already tested:

completely recreated Assets.car using Xcode
all required icon sizes added correctly
no transparency in PNGs
valid 120x120 icon included
Assets.car exists only once in the IPA
file is located correctly in the app root
CFBundleIconName set to AppIcon
tested renderMode="gpu" and renderMode="direct"
no ANEs used
re-signing IPA manually
tested on real devices

My AIR XML currently contains:

<iPhone>
    <assetsCar>Assets.car</assetsCar>
    <requestedDisplayResolution>high</requestedDisplayResolution>

    <InfoAdditions><![CDATA[
        <key>CFBundleIconName</key>
        <string>AppIcon</string>
    ]]></InfoAdditions>
</iPhone>

Important:
If I REMOVE Assets.car and instead use classic PNG icons inside the <icon> tag, the app works perfectly on the device.

However, App Store Connect / Transporter then rejects the IPA with:

“Missing required icon file. The bundle does not contain an app icon of exactly 120x120 pixels…”

even though the 120x120 PNG definitely exists and is correctly referenced.

So currently I am stuck between:

Assets.car → App crashes
classic PNG icons → Upload rejected by Apple

I also found multiple reports describing similar regressions in AIR 51.2.x / 51.3.x with iOS 18+:

AIR apps crashing immediately after launch with “application packaging error”
issues related to Assets.car packaging/runtime lookup

Examples:

Has anyone found a stable workflow for:

AIR 51.3.x
Xcode 26
iOS 18+
App Store compliant icon packaging?

Or is this currently a confirmed AIR runtime regression?

Any help would be greatly appreciated because at the moment it is impossible to both:

upload successfully to App Store Connect
AND
launch the app successfully on-device.

Thanks!