[BUG] Claude Desktop 1.26832.0.0 — MSIX installs successfully but reports "Modified, NeedsRemediation"; app cannot launch (Windows 11 26200)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Claude Desktop 1.26832.0.0 installs successfully on Windows 11 Pro (10.0.26200, x64) but cannot launch. Immediately after a clean install, Get-AppxPackage reports the package Status as "Modified, NeedsRemediation", and launching produces the Windows dialog:

"Can't open this app — You'll need to go to advanced options for Claude and select Repair. If you're still having issues with it, reinstall this app or contact your administrator."

The installer itself reports complete success: Authenticode signature verified, "MSIX installation succeeded", elevated process exits with code 0. The failure is in Windows' package integrity verification after staging, not in the install.

Reproduced across two fully independent download + install cycles with a complete uninstall, leftover-folder deletion and reboot in between.

What Should Happen?

Claude Desktop should launch to the sign-in screen after installation.

Error Messages/Logs

Post-install package state:

Get-AppxPackage Status : Modified, NeedsRemediation
Version                : 1.26832.0.0
InstallLocation        : C:\Program Files\WindowsApps\Claude_1.26832.0.0_x64__pzs8sxrjxfjjc
SignatureKind          : Developer
Manifest entry point   : Id = Claude, Executable = app\Claude.exe
EXE exists on disk     : True

--- ClaudeSetup.log, attempt 1 ---
2026/08/11 15:33:15.019612 Download complete: 266210150 bytes, SHA256: 6dc210bca31b55c9fa307d11c6b13a42c7f3a3886ccc35ca2ecb7e9fceba0139
2026/08/11 15:33:15.163788 Windows edition: Professional
2026/08/11 15:33:15.164916 Windows version: 10.0.26200
2026/08/11 15:33:15.164916 Native arch: x64
2026/08/11 15:33:15.164916 Elevation type: Full
2026/08/11 15:33:15.164916 Is elevated: true
2026/08/11 15:33:15.164916 Sideloading enabled: true
2026/08/11 15:33:15.164916 S Mode: false
2026/08/11 15:33:15.164916 Conflicting service: false
2026/08/11 15:33:15.164916 Installing MSIX from C:\Users\USERX~1\AppData\Local\Temp\Claude-550563997.msix (all-users: false)
2026/08/11 15:33:16.374607 WinVerifyTrust: MSIX signature is valid
2026/08/11 15:33:16.871398 Signature verified: MSIX signer matches bootstrapper
2026/08/11 15:33:16.873152 Squirrel process prefix: c:\users\user x\appdata\local\anthropicclaude\
2026/08/11 15:33:16.902738 Standard install (not split-account), using AddPackage
2026/08/11 15:33:16.902738 Installing via AddPackage (current-user)...
2026/08/11 15:33:24.154726 MSIX package installed successfully
2026/08/11 15:33:24.188168 MSIX installation succeeded
2026/08/11 15:33:24.266339 Launching Claude via explorer.exe shell:AppsFolder\Claude_pzs8sxrjxfjjc!Claude
2026/08/11 15:33:24.297058 === Claude Setup completed successfully ===
2026/08/11 15:33:24.320672 Elevated process exited with code 0

--- ClaudeSetup.log, attempt 2 (after full uninstall + reboot) ---
2026/08/11 16:12:42.197252 Sideloading enabled: true
2026/08/11 16:12:42.197252 S Mode: false
2026/08/11 16:12:42.197252 Conflicting service: false
2026/08/11 16:12:42.197252 Running in elevated context
2026/08/11 16:12:42.197836 Installing MSIX from C:\Users\USERX~1\AppData\Local\Temp\Claude-1336857950.msix (all-users: false)
2026/08/11 16:12:44.184970 WinVerifyTrust: MSIX signature is valid
2026/08/11 16:12:45.086468 Signature verified: MSIX signer matches bootstrapper
2026/08/11 16:12:45.089796 Squirrel process prefix: c:\users\user x\appdata\local\anthropicclaude\
2026/08/11 16:12:45.130342 Standard install (not split-account), using AddPackage
2026/08/11 16:12:45.130342 Installing via AddPackage (current-user)...
2026/08/11 16:13:04.132267 MSIX package installed successfully
2026/08/11 16:13:04.171833 MSIX installation succeeded
2026/08/11 16:13:04.233087 Launching Claude via explorer.exe shell:AppsFolder\Claude_pzs8sxrjxfjjc!Claude
2026/08/11 16:13:04.277450 === Claude Setup completed successfully ===
2026/08/11 16:13:04.302576 Elevated process exited with code 0

Steps to Reproduce

1. Remove any existing install:

Get-AppxPackage -Name Claude | Remove-AppxPackage

1. Delete leftover folders:

%LOCALAPPDATA%\Packages\Claude_pzs8sxrjxfjjc
%APPDATA%\Claude

1. Confirm removal — Get-AppxPackage -Name Claude returns nothing.
2. Restart Windows (full Restart, not Shut down).
3. Download the installer from claude.ai/download.
4. Right-click the installer, choose "Run as administrator", approve the UAC prompt.
5. Installer reports success and attempts to launch Claude.
6. "Can't open this app" dialog appears.
7. Check status: (Get-AppxPackage -Name Claude).Status

Returns: Modified, NeedsRemediation

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

Unknown — app was working prior to an auto-update

Claude Code Version

Claude Desktop 1.26832.0.0 (not Claude Code — this is a Desktop app issue)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

Confirming this on a second machine — Windows 11 Pro 10.0.26200 x64, Claude Desktop 1.26832.0.0.
Same symptom: install log clean (signature verified, exit code 0), package immediately reports
Modified, NeedsRemediation, app won't launch. Reproduced across two independent download and
install cycles with a full uninstall and reboot in between. Details below.

Remediation attempted — all unsuccessful:

• Settings > Advanced options > Repair → "We couldn't repair this app. Try again in a bit."
• Settings > Advanced options > Reset → no effect
• Reset-AppxPackage → completes silently with no error; status unchanged
• Activation via shell:AppsFolder\Claude_pzs8sxrjxfjjc!Claude → same dialog
• Full uninstall + folder cleanup + reboot + fresh download and install → reproduces identically
• Direct Add-AppxPackage from the MSIX → not possible, the bootstrapper deletes the MSIX from Temp after installing

Ruled out:

• No third-party antivirus — Windows Defender only
• Get-MpThreatDetection → zero detections
• Controlled Folder Access → disabled (0)
• hns and vmcompute services → both Running
• Sideloading enabled: true; S Mode: false; Conflicting service: false
• Installer ran elevated (Is elevated: true, Elevation type: Full)
• No stale Squirrel install ("No Squirrel installation found, skipping uninstall")

Observations:

1. Both installs report complete success. The entry point exists and app\Claude.exe is present on disk, so this does not appear to be the missing-entry-point failure reported elsewhere.
2. Staging duration differed between attempts on the same machine — roughly 8s (15:33:16 → 15:33:24) vs roughly 19s (16:12:45 → 16:13:04). Possibly suggests something non-deterministic in the write path rather than a fixed packaging defect.
3. Reset-AppxPackage is the documented remedy for NeedsRemediation and completes without error, yet the flag persists — suggesting the re-staged content also fails verification.
4. Environment note: the Windows username contains a space, so the profile path resolves through the 8.3 short name USERX~1. The log shows the Squirrel prefix as "c:\users\user x\appdata\local\anthropicclaude\" while the MSIX source path is written as "C:\Users\USERX~1\AppData\Local\Temp\...". This is the only non-standard aspect of the environment and may be worth checking in the MSIX staging path logic.

Impact: Claude Desktop is completely unusable on this machine. Browser access to claude.ai works normally.