09-29 22:09:33.231 ... avc: denied { read } for ... name="u:object_r:userdebug_or_eng_prop:s0" ... app=com.microsoft.office.outlook
09-29 22:09:33.511 ... avc: denied { read } for ... name="u:object_r:odsign_prop:s0" ... app=com.microsoft.office.outlook
09-29 22:09:33.739 ... avc: denied { read } for ... name="u:object_r:build_attestation_prop:s0" ... app=com.microsoft.office.outlook

Summary of the Issue

I am unable to log into the Outlook for Android app on my device running GrapheneOS. After entering my email address, the app proceeds to the password screen but immediately displays a misleading network error, preventing me from entering my password and completing the login. My device's network connection is fully functional.

Steps to Reproduce

Install the latest version of the Outlook app from the Google Play Store.

Open the app and tap "Add Account."

Enter a valid Microsoft/Outlook email address and tap "Continue."

The app attempts to load the password entry screen.

Expected Result

The app should display a password field, allowing me to enter my password, perform multi-factor authentication, and successfully log in.

Actual Result

The app immediately displays an error message overlaying the screen: "No network connection. Please check your network settings and try again.". It is impossible to enter a password or proceed.

Technical Details & Diagnosis

This does not appear to be a network issue, but rather a security-related incompatibility between the app and the operating system.

Operating System: GrapheneOS (google/cheetah/cheetah:16/BP2A.250805.005/2025092700:user/release-keys)

App Version: com.microsoft.office.outlook:42535826

Root Cause Analysis: A device logcat captured during the login attempt shows numerous SELinux denials. The operating system is blocking the Outlook app from reading specific system properties related to device integrity and build status.

Key lines from the logcat:

avc: denied { read } for comm="app_process64" name="u:object_r:userdebug_or_eng_prop:s0" ... app=com.microsoft.office.outlook

avc: denied { read } for comm="main" name="u:object_r:build_attestation_prop:s0" ... app=com.microsoft.office.outlook

This indicates the app's authentication library is likely performing a device integrity check that is incompatible with the security policies of this Android version, causing the process to fail and fall back to a generic network error.

Troubleshooting Steps Already Taken

The following standard troubleshooting steps have been performed and did not resolve the issue:

Confirmed full internet access via both Wi-Fi and Mobile Data.

Restarted the device multiple times.

Cleared the Outlook app's cache and storage.

Uninstalled and reinstalled the Outlook app.

Enabled GrapheneOS's per-app "Exploit Protection Compatibility Mode" for Outlook and rebooted.

Thank you for your time and assistance.