### Preflight Checklist - [x] I have searched [existing issues](https://github.com/anthropics/claude-code/issues?q=is%3Aissue%20state%3Aopen%20label%3Abug) 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? When I try to install Claude application using latest CLaude Setup evey time i am getting trouble with unknown error 0x80073CFF <img width="607" height=

[BUG] error 0x80073CFF Claude Setup

Status Closed — not planned
Maintainer reply None cached
Activity 1 comment · opened Sep 3, 2026 · closed Sep 6, 2026
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?

When I try to install Claude application using latest CLaude Setup evey time i am getting trouble with unknown error 0x80073CFF
What Should Happen?

Claude application installed
Error Messages/Logs

2026/09/03 11:20:22.895789 Log file: C:\Users\admin\AppData\Local\Temp\ClaudeSetup.log
2026/09/03 11:20:22.911025 === Claude Setup 0d57a2f7d9b22cb8cd8804faae00208185608888 started ===
2026/09/03 11:20:22.911025 AllowDevelopmentWithoutDevLicense found with value: 1
2026/09/03 11:20:22.911025 Windows edition: Professional
2026/09/03 11:20:22.911593 Windows version: 10.0.26200
2026/09/03 11:20:22.911593 Native arch: x64
2026/09/03 11:20:22.911593 Elevation type: Limited
2026/09/03 11:20:22.911593 Is elevated: false
2026/09/03 11:20:22.912107 Sideloading enabled: true
2026/09/03 11:20:22.912107 S Mode: false
2026/09/03 11:20:22.912107 Conflicting service: false
2026/09/03 11:20:22.912107 Running in non-elevated context
2026/09/03 11:20:22.912107 User can elevate — installing MSIX directly
2026/09/03 11:20:22.929610 Splash: 400x300, 8 frame(s), animated=true
2026/09/03 11:20:22.929610 System DPI: 120 (scale: 125%)
2026/09/03 11:20:22.974535 MSIX URL: https://api.anthropic.com/api/desktop/win32/x64/msix/latest/redirect
2026/09/03 11:20:22.975042 Downloading MSIX to C:\Users\admin\AppData\Local\Temp\Claude-1604186182.msix
2026/09/03 11:20:22.986758 proxy: WinHttpGetProxyForUrl("https://api.anthropic.com/api/desktop/win32/x64/msix/latest/redirect"): winapi error #12180
2026/09/03 11:20:23.389744 proxy: WinHttpGetProxyForUrl("https://downloads.claude.ai/releases/win32/x64/1.44121.4/Claude-0d57a2f7d9b22cb8cd8804faae00208185608888.msix"): winapi error #12180
2026/09/03 11:20:35.739447 Download progress: 10% (26525632 / 264936762 bytes)
2026/09/03 11:20:36.467111 Download progress: 20% (53001968 / 264936762 bytes)
2026/09/03 11:20:37.342680 Download progress: 30% (79494576 / 264936762 bytes)
2026/09/03 11:20:37.973707 Download progress: 40% (106004096 / 264936762 bytes)
2026/09/03 11:20:38.589077 Download progress: 50% (132480048 / 264936762 bytes)
2026/09/03 11:20:39.171560 Download progress: 60% (158973136 / 264936762 bytes)
2026/09/03 11:20:39.658745 Download progress: 70% (185465632 / 264936762 bytes)
2026/09/03 11:20:40.289694 Download progress: 80% (211958224 / 264936762 bytes)
2026/09/03 11:20:40.912786 Download progress: 90% (238467568 / 264936762 bytes)
2026/09/03 11:20:41.781887 Download progress: 100% (264936762 / 264936762 bytes)
2026/09/03 11:20:41.783037 Download complete: 264936762 bytes, SHA256: 332639f6435a71b59de4b609f4ac437fab56f40db2c59d535ea1e04b0f0b1fe4
2026/09/03 11:20:41.783551 Download complete
2026/09/03 11:20:41.804822 Self-elevating: C:\Users\admin\Desktop\Claude Setup.exe --elevated --msix-path "C:\Users\admin\AppData\Local\Temp\Claude-1604186182.msix" --log-path "C:\Users\admin\AppData\Local\Temp\ClaudeSetup.log"
2026/09/03 11:20:42.063829 Waiting for elevated process to complete...
2026/09/03 11:20:42.071507 Log file: C:\Users\admin\AppData\Local\Temp\ClaudeSetup.log
2026/09/03 11:20:42.084719 === Claude Setup 0d57a2f7d9b22cb8cd8804faae00208185608888 started ===
2026/09/03 11:20:42.084719 AllowDevelopmentWithoutDevLicense found with value: 1
2026/09/03 11:20:42.084719 Windows edition: Professional
2026/09/03 11:20:42.085339 Windows version: 10.0.26200
2026/09/03 11:20:42.085339 Native arch: x64
2026/09/03 11:20:42.085339 Elevation type: Full
2026/09/03 11:20:42.085339 Is elevated: true
2026/09/03 11:20:42.085339 Sideloading enabled: true
2026/09/03 11:20:42.085339 S Mode: false
2026/09/03 11:20:42.085339 Conflicting service: false
2026/09/03 11:20:42.085339 Running in elevated context
2026/09/03 11:20:42.085339 Installing MSIX from C:\Users\admin\AppData\Local\Temp\Claude-1604186182.msix (all-users: false)
2026/09/03 11:20:42.101546 Splash: 400x300, 8 frame(s), animated=true
2026/09/03 11:20:42.101546 System DPI: 120 (scale: 125%)
2026/09/03 11:20:42.136333 Verifying Authenticode signature on C:\Users\admin\AppData\Local\Temp\Claude-1604186182.msix
2026/09/03 11:20:43.177377 WinVerifyTrust: MSIX signature is valid
2026/09/03 11:20:43.707611 Signature verified: MSIX signer matches bootstrapper
2026/09/03 11:20:43.710733 Extracted family name from MSIX manifest: Claude_pzs8sxrjxfjjc
2026/09/03 11:20:43.710733 Squirrel process prefix: c:\users\admin\appdata\local\anthropicclaude\
2026/09/03 11:20:43.710733 Checking for running Squirrel Claude processes...
2026/09/03 11:20:43.717617 No Squirrel Claude processes found
2026/09/03 11:20:43.717617 Checking for existing Claude MSIX packages...
2026/09/03 11:20:43.732950 Installing MSIX: C:\Users\admin\AppData\Local\Temp\Claude-1604186182.msix
2026/09/03 11:20:43.732950 Standard install (not split-account), using AddPackage
2026/09/03 11:20:43.732950 Installing via AddPackage (current-user)...
2026/09/03 11:20:44.750300 MSIX installation failed: AddPackage failed: AddPackage failed with HRESULT 0x80073CFF
2026/09/03 11:20:44.750300 ERROR dialog (opening log): Installation failed: AddPackage failed: AddPackage failed with HRESULT 0x80073CFF

Please share this log with us.
2026/09/03 11:20:52.970157 Elevated process exited with code 1
2026/09/03 11:20:52.970157 Elevation failed: elevated installer exited with code 1
2026/09/03 11:20:52.970157 ERROR dialog (with log path): Administrator access is required to install Claude with full features. You can try again or install without Cowork.
2026/09/03 11:25:45.206228 Log file: C:\Users\admin\AppData\Local\Temp\ClaudeSetup.log
2026/09/03 11:25:45.221580 === Claude Setup 0d57a2f7d9b22cb8cd8804faae00208185608888 started ===
2026/09/03 11:25:45.221580 AllowDevelopmentWithoutDevLicense found with value: 1
2026/09/03 11:25:45.221580 Windows edition: Professional
2026/09/03 11:25:45.222138 Windows version: 10.0.26200
2026/09/03 11:25:45.222138 Native arch: x64
2026/09/03 11:25:45.222138 Elevation type: Limited
2026/09/03 11:25:45.222138 Is elevated: false
2026/09/03 11:25:45.222138 Sideloading enabled: true
2026/09/03 11:25:45.222138 S Mode: false
2026/09/03 11:25:45.222138 Conflicting service: false
2026/09/03 11:25:45.222138 Running in non-elevated context
2026/09/03 11:25:45.222138 User can elevate — installing MSIX directly
2026/09/03 11:25:45.239939 Splash: 400x300, 8 frame(s), animated=true
2026/09/03 11:25:45.239939 System DPI: 120 (scale: 125%)
2026/09/03 11:25:45.276375 MSIX URL: https://api.anthropic.com/api/desktop/win32/x64/msix/latest/redirect
2026/09/03 11:25:45.276375 Downloading MSIX to C:\Users\admin\AppData\Local\Temp\Claude-3703151430.msix
2026/09/03 11:25:45.288179 proxy: WinHttpGetProxyForUrl("https://api.anthropic.com/api/desktop/win32/x64/msix/latest/redirect"): winapi error #12180
2026/09/03 11:25:56.832111 proxy: WinHttpGetProxyForUrl("https://downloads.claude.ai/releases/win32/x64/1.44121.4/Claude-0d57a2f7d9b22cb8cd8804faae00208185608888.msix"): winapi error #12180
2026/09/03 11:26:09.567784 Download progress: 10% (26525632 / 264936762 bytes)
2026/09/03 11:26:12.074404 Download progress: 20% (53001632 / 264936762 bytes)
2026/09/03 11:26:12.920565 Download progress: 30% (79494992 / 264936762 bytes)
2026/09/03 11:26:14.007087 Download progress: 40% (105986720 / 264936762 bytes)
2026/09/03 11:26:14.952089 Download progress: 50% (132496400 / 264936762 bytes)
2026/09/03 11:26:16.327550 Download progress: 60% (158972304 / 264936762 bytes)
2026/09/03 11:26:17.319446 Download progress: 70% (185465664 / 264936762 bytes)
2026/09/03 11:26:18.161910 Download progress: 80% (211975072 / 264936762 bytes)
2026/09/03 11:26:19.500262 Download progress: 90% (238451216 / 264936762 bytes)
2026/09/03 11:26:20.519875 Download progress: 100% (264936762 / 264936762 bytes)
2026/09/03 11:26:20.520988 Download complete: 264936762 bytes, SHA256: 332639f6435a71b59de4b609f4ac437fab56f40db2c59d535ea1e04b0f0b1fe4
2026/09/03 11:26:20.521510 Download complete
2026/09/03 11:26:20.532742 Self-elevating: C:\Users\admin\Desktop\Claude Setup (1).exe --elevated --msix-path "C:\Users\admin\AppData\Local\Temp\Claude-3703151430.msix" --log-path "C:\Users\admin\AppData\Local\Temp\ClaudeSetup.log"
2026/09/03 11:26:21.004972 Waiting for elevated process to complete...
2026/09/03 11:26:21.010775 Log file: C:\Users\admin\AppData\Local\Temp\ClaudeSetup.log
2026/09/03 11:26:21.027028 === Claude Setup 0d57a2f7d9b22cb8cd8804faae00208185608888 started ===
2026/09/03 11:26:21.027028 AllowDevelopmentWithoutDevLicense found with value: 1
2026/09/03 11:26:21.027028 Windows edition: Professional
2026/09/03 11:26:21.027576 Windows version: 10.0.26200
2026/09/03 11:26:21.028144 Native arch: x64
2026/09/03 11:26:21.028144 Elevation type: Full
2026/09/03 11:26:21.028144 Is elevated: true
2026/09/03 11:26:21.028144 Sideloading enabled: true
2026/09/03 11:26:21.028144 S Mode: false
2026/09/03 11:26:21.028144 Conflicting service: false
2026/09/03 11:26:21.028144 Running in elevated context
2026/09/03 11:26:21.028144 Installing MSIX from C:\Users\admin\AppData\Local\Temp\Claude-3703151430.msix (all-users: false)
2026/09/03 11:26:21.045227 Splash: 400x300, 8 frame(s), animated=true
2026/09/03 11:26:21.045227 System DPI: 120 (scale: 125%)
2026/09/03 11:26:21.073250 Verifying Authenticode signature on C:\Users\admin\AppData\Local\Temp\Claude-3703151430.msix
2026/09/03 11:26:22.090910 WinVerifyTrust: MSIX signature is valid
2026/09/03 11:26:22.619483 Signature verified: MSIX signer matches bootstrapper
2026/09/03 11:26:22.621843 Extracted family name from MSIX manifest: Claude_pzs8sxrjxfjjc
2026/09/03 11:26:22.621843 Squirrel process prefix: c:\users\admin\appdata\local\anthropicclaude\
2026/09/03 11:26:22.621843 Checking for running Squirrel Claude processes...
2026/09/03 11:26:22.628317 No Squirrel Claude processes found
2026/09/03 11:26:22.628317 Checking for existing Claude MSIX packages...
2026/09/03 11:26:22.657392 Installing MSIX: C:\Users\admin\AppData\Local\Temp\Claude-3703151430.msix
2026/09/03 11:26:22.657392 Standard install (not split-account), using AddPackage
2026/09/03 11:26:22.657392 Installing via AddPackage (current-user)...
2026/09/03 11:26:23.431536 MSIX installation failed: AddPackage failed: AddPackage failed with HRESULT 0x80073CFF
2026/09/03 11:26:23.431536 ERROR dialog (opening log): Installation failed: AddPackage failed: AddPackage failed with HRESULT 0x80073CFF

Please share this log with us.
2026/09/03 11:27:02.069423 Log file: C:\Users\admin\AppData\Local\Temp\ClaudeSetup.log
2026/09/03 11:27:02.085065 === Claude Setup 0d57a2f7d9b22cb8cd8804faae00208185608888 started ===
2026/09/03 11:27:02.085065 AllowDevelopmentWithoutDevLicense found with value: 1
2026/09/03 11:27:02.085065 Windows edition: Professional
2026/09/03 11:27:02.085614 Windows version: 10.0.26200
2026/09/03 11:27:02.085614 Native arch: x64
2026/09/03 11:27:02.085614 Elevation type: Full
2026/09/03 11:27:02.085614 Is elevated: true
2026/09/03 11:27:02.085614 Sideloading enabled: true
2026/09/03 11:27:02.085614 S Mode: false
2026/09/03 11:27:02.085614 Conflicting service: false
2026/09/03 11:27:02.085614 Running in non-elevated context
2026/09/03 11:27:02.085614 User can elevate — installing MSIX directly
2026/09/03 11:27:02.102921 Splash: 400x300, 8 frame(s), animated=true
2026/09/03 11:27:02.102921 System DPI: 120 (scale: 125%)
2026/09/03 11:27:02.133099 MSIX URL: https://api.anthropic.com/api/desktop/win32/x64/msix/latest/redirect
2026/09/03 11:27:02.133099 Downloading MSIX to C:\Users\admin\AppData\Local\Temp\Claude-3404828336.msix
2026/09/03 11:27:02.145255 proxy: WinHttpGetProxyForUrl("https://api.anthropic.com/api/desktop/win32/x64/msix/latest/redirect"): winapi error #12180
2026/09/03 11:27:13.638719 proxy: WinHttpGetProxyForUrl("https://downloads.claude.ai/releases/win32/x64/1.44121.4/Claude-0d57a2f7d9b22cb8cd8804faae00208185608888.msix"): winapi error #12180
2026/09/03 11:27:15.721282 Download progress: 10% (26509280 / 264936762 bytes)
2026/09/03 11:27:16.718342 Download progress: 20% (53001632 / 264936762 bytes)
2026/09/03 11:27:19.146878 Download progress: 30% (79494576 / 264936762 bytes)
2026/09/03 11:27:22.702534 Download progress: 40% (106003872 / 264936762 bytes)
2026/09/03 11:27:25.733500 Download progress: 50% (132480176 / 264936762 bytes)
2026/09/03 11:27:26.547313 Download progress: 60% (158973328 / 264936762 bytes)
2026/09/03 11:27:27.387475 Download progress: 70% (185465792 / 264936762 bytes)
2026/09/03 11:27:28.299060 Download progress: 80% (211958224 / 264936762 bytes)
2026/09/03 11:27:29.165391 Download progress: 90% (238467568 / 264936762 bytes)
2026/09/03 11:27:30.086079 Download progress: 100% (264936762 / 264936762 bytes)
2026/09/03 11:27:30.087101 Download complete: 264936762 bytes, SHA256: 332639f6435a71b59de4b609f4ac437fab56f40db2c59d535ea1e04b0f0b1fe4
2026/09/03 11:27:30.087699 Download complete
2026/09/03 11:27:30.094545 Self-elevating: C:\Users\admin\Desktop\Claude Setup (1).exe --elevated --msix-path "C:\Users\admin\AppData\Local\Temp\Claude-3404828336.msix" --log-path "C:\Users\admin\AppData\Local\Temp\ClaudeSetup.log"
2026/09/03 11:27:30.153881 Waiting for elevated process to complete...
2026/09/03 11:27:30.164269 Log file: C:\Users\admin\AppData\Local\Temp\ClaudeSetup.log
2026/09/03 11:27:30.178377 === Claude Setup 0d57a2f7d9b22cb8cd8804faae00208185608888 started ===
2026/09/03 11:27:30.178377 AllowDevelopmentWithoutDevLicense found with value: 1
2026/09/03 11:27:30.178377 Windows edition: Professional
2026/09/03 11:27:30.178942 Windows version: 10.0.26200
2026/09/03 11:27:30.178942 Native arch: x64
2026/09/03 11:27:30.178942 Elevation type: Full
2026/09/03 11:27:30.178942 Is elevated: true
2026/09/03 11:27:30.178942 Sideloading enabled: true
2026/09/03 11:27:30.178942 S Mode: false
2026/09/03 11:27:30.178942 Conflicting service: false
2026/09/03 11:27:30.178942 Running in elevated context
2026/09/03 11:27:30.178942 Installing MSIX from C:\Users\admin\AppData\Local\Temp\Claude-3404828336.msix (all-users: false)
2026/09/03 11:27:30.196540 Splash: 400x300, 8 frame(s), animated=true
2026/09/03 11:27:30.196540 System DPI: 120 (scale: 125%)
2026/09/03 11:27:30.220123 Verifying Authenticode signature on C:\Users\admin\AppData\Local\Temp\Claude-3404828336.msix
2026/09/03 11:27:31.252316 WinVerifyTrust: MSIX signature is valid
2026/09/03 11:27:31.804450 Signature verified: MSIX signer matches bootstrapper
2026/09/03 11:27:31.806835 Extracted family name from MSIX manifest: Claude_pzs8sxrjxfjjc
2026/09/03 11:27:31.806835 Squirrel process prefix: c:\users\admin\appdata\local\anthropicclaude\
2026/09/03 11:27:31.806835 Checking for running Squirrel Claude processes...
2026/09/03 11:27:31.812798 No Squirrel Claude processes found
2026/09/03 11:27:31.812798 Checking for existing Claude MSIX packages...
2026/09/03 11:27:31.827504 Installing MSIX: C:\Users\admin\AppData\Local\Temp\Claude-3404828336.msix
2026/09/03 11:27:31.827504 Standard install (not split-account), using AddPackage
2026/09/03 11:27:31.827504 Installing via AddPackage (current-user)...
2026/09/03 11:27:32.341395 MSIX installation failed: AddPackage failed: AddPackage failed with HRESULT 0x80073CFF
2026/09/03 11:27:32.341395 ERROR dialog (opening log): Installation failed: AddPackage failed: AddPackage failed with HRESULT 0x80073CFF

Please share this log with us.
2026/09/03 11:27:39.440134 Elevated process exited with code 1
2026/09/03 11:27:39.440134 Elevation failed: elevated installer exited with code 1
2026/09/03 11:27:39.440134 ERROR dialog (with log path): Administrator access is required to install Claude with full features. You can try again or install without Cowork.
2026/09/03 11:27:41.650223 Elevated process exited with code 1
2026/09/03 11:27:41.650223 Elevation failed: elevated installer exited with code 1
2026/09/03 11:27:41.650223 ERROR dialog (with log path): Administrator access is required to install Claude with full features. You can try again or install without Cowork.
Steps to Reproduce

1.Download Claude Setup
2.Run it.
Claude Model

None
Is this a regression?

I don't know
Last Working Version

_No response_
Claude Code Version

latest
Platform

Anthropic API
Operating System

Windows
Terminal/Shell

Other
Additional Information
