Description
When using AltServer.app on macOS 26.1 with an iPhone 17 running iOS 26.1, attempting to Deactivate (uninstall) an app from AltStore via USB connection consistently causes AltServer on macOS to crash as soon as the process reaches the Backup step.
AltStore then shows:
- AltServer.ServerError 2002 (when using USB)
- AltServer.Operation Error 1200 (when attempting the same over Wi-Fi — though Wi-Fi fails immediately before any backup begins)
The issue occurs every time and is fully reproducible.
Steps to Reproduce
- Launch AltServer.app on macOS 26.1
- Connect an iPhone 17 (iOS 26.1) via USB
- Open AltStore on the iPhone
- Select any installed app
- Tap Deactivate
- When the operation reaches the Backing up… phase
- AltServer immediately crashes, and AltStore displays ServerError 2002
Attempting the same operation over Wi-Fi results in Operation Error 1200 immediately without reaching the backup step.
Expected Behavior
AltServer.app should successfully execute the backup step and complete the deactivation without crashing or losing connection.
Actual Behavior
- AltServer crashes instantly during the Backup step when connected via USB
- AltStore shows:
AltServer.ServerError 2002 — Lost connection to AltServer
- When using Wi-Fi instead, the operation fails immediately with:
AltServer.Operation Error 1200
Environment
- Mac model: Mac mini (M4, 2024)
- macOS: 26.1
- AltServer: 1.7.2 (90)
- Device: iPhone 17
- iOS: 26.1
- AltStore (on device): 2.2.1
- Connection: Type-C USB 4 40Gbps cable
Additional Context
- Issue is reproducible 100% of the time
- I can provide AltServer app logs and AltServer.app crash video if needed