diff --git a/codex-rs/tui/src/app.rs b/codex-rs/tui/src/app.rs
index 9fd9ae5b9..0e878aafb 100644
--- a/codex-rs/tui/src/app.rs
+++ b/codex-rs/tui/src/app.rs
@@ -3,8 +3,6 @@ use crate::app_event::AppEvent;
 use crate::app_event::ExitMode;
 #[cfg(target_os = "windows")]
 use crate::app_event::WindowsSandboxEnableMode;
-#[cfg(target_os = "windows")]
-use crate::app_event::WindowsSandboxFallbackReason;
 use crate::app_event_sender::AppEventSender;
 use crate::bottom_pane::ApprovalRequest;
 use crate::bottom_pane::FeedbackAudience;
@@ -1707,7 +1705,7 @@ impl App {
             AppEvent::OpenWindowsSandboxEnablePrompt { preset } => {
                 self.chat_widget.open_windows_sandbox_enable_prompt(preset);
             }
-            AppEvent::OpenWindowsSandboxFallbackPrompt { preset, reason } => {
+            AppEvent::OpenWindowsSandboxFallbackPrompt { preset } => {
                 self.otel_manager
                     .counter("codex.windows_sandbox.fallback_prompt_shown", 1, &[]);
                 self.chat_widget.clear_windows_sandbox_setup_status();
@@ -1719,7 +1717,7 @@ impl App {
                     );
                 }
                 self.chat_widget
-                    .open_windows_sandbox_fallback_prompt(preset, reason);
+                    .open_windows_sandbox_fallback_prompt(preset);
             }
             AppEvent::BeginWindowsSandboxElevatedSetup { preset } => {
                 #[cfg(target_os = "windows")]
@@ -1795,10 +1793,7 @@ impl App {
                                     error = %err,
                                     "failed to run elevated Windows sandbox setup"
                                 );
-                                AppEvent::OpenWindowsSandboxFallbackPrompt {
-                                    preset,
-                                    reason: WindowsSandboxFallbackReason::ElevationFailed,
-                                }
+                                AppEvent::OpenWindowsSandboxFallbackPrompt { preset }
                             }
                         };
                         tx.send(event);
@@ -1819,6 +1814,7 @@ impl App {
                         std::env::vars().collect();
                     let codex_home = self.config.codex_home.clone();
                     let tx = self.app_event_tx.clone();
+                    let otel_manager = self.otel_manager.clone();
 
                     self.chat_widget.show_windows_sandbox_setup_status();
                     tokio::task::spawn_blocking(move || {
@@ -1829,6 +1825,11 @@ impl App {
                             &env_map,
                             codex_home.as_path(),
                         ) {
+                            otel_manager.counter(
+                                "codex.windows_sandbox.legacy_setup_preflight_failed",
+                                1,
+                                &[],
+                            );
                             tracing::warn!(
                                 error = %err,
                                 "failed to preflight non-admin Windows sandbox setup"
diff --git a/codex-rs/tui/src/app_event.rs b/codex-rs/tui/src/app_event.rs
index c04665eb2..8bf3ab370 100644
--- a/codex-rs/tui/src/app_event.rs
+++ b/codex-rs/tui/src/app_event.rs
@@ -36,13 +36,8 @@ pub(crate) enum WindowsSandboxEnableMode {
     Legacy,
 }
 
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
-#[cfg_attr(not(target_os = "windows"), allow(dead_code))]
-pub(crate) enum WindowsSandboxFallbackReason {
-    ElevationFailed,
-}
-
 #[derive(Debug, Clone)]
+#[cfg_attr(not(target_os = "windows"), allow(dead_code))]
 pub(crate) struct ConnectorsSnapshot {
     pub(crate) connectors: Vec<AppInfo>,
 }
@@ -205,7 +200,6 @@ pub(crate) enum AppEvent {
     #[cfg_attr(not(target_os = "windows"), allow(dead_code))]
     OpenWindowsSandboxFallbackPrompt {
         preset: ApprovalPreset,
-        reason: WindowsSandboxFallbackReason,
     },
 
     /// Begin the elevated Windows sandbox setup flow.
diff --git a/codex-rs/tui/src/chatwidget.rs b/codex-rs/tui/src/chatwidget.rs
index 81c9faed6..b2b064378 100644
--- a/codex-rs/tui/src/chatwidget.rs
+++ b/codex-rs/tui/src/chatwidget.rs
@@ -162,7 +162,6 @@ use crate::app_event::ConnectorsSnapshot;
 use crate::app_event::ExitMode;
 #[cfg(target_os = "windows")]
 use crate::app_event::WindowsSandboxEnableMode;
-use crate::app_event::WindowsSandboxFallbackReason;
 use crate::app_event_sender::AppEventSender;
 use crate::bottom_pane::ApprovalRequest;
 use crate::bottom_pane::BottomPane;
@@ -5738,7 +5737,7 @@ impl ChatWidget {
                 name: "Use non-admin sandbox (higher risk if prompt injected)".to_string(),
                 description: None,
                 actions: vec![Box::new(move |tx| {
-                    legacy_otel.counter("codex.windows_sandbox.fallback_use_legacy", 1, &[]);
+                    legacy_otel.counter("codex.windows_sandbox.elevated_prompt_use_legacy", 1, &[]);
                     tx.send(AppEvent::BeginWindowsSandboxLegacySetup {
                         preset: legacy_preset.clone(),
                     });
@@ -5750,7 +5749,7 @@ impl ChatWidget {
                 name: "Quit".to_string(),
                 description: None,
                 actions: vec![Box::new(move |tx| {
-                    quit_otel.counter("codex.windows_sandbox.elevated_prompt_decline", 1, &[]);
+                    quit_otel.counter("codex.windows_sandbox.elevated_prompt_quit", 1, &[]);
                     tx.send(AppEvent::Exit(ExitMode::ShutdownFirst));
                 })],
                 dismiss_on_select: true,
@@ -5771,15 +5770,9 @@ impl ChatWidget {
     pub(crate) fn open_windows_sandbox_enable_prompt(&mut self, _preset: ApprovalPreset) {}
 
     #[cfg(target_os = "windows")]
-    pub(crate) fn open_windows_sandbox_fallback_prompt(
-        &mut self,
-        preset: ApprovalPreset,
-        reason: WindowsSandboxFallbackReason,
-    ) {
+    pub(crate) fn open_windows_sandbox_fallback_prompt(&mut self, preset: ApprovalPreset) {
         use ratatui_macros::line;
 
-        let _ = reason;
-
         let mut lines = Vec::new();
         lines.push(line![
             "Couldn't set up your sandbox with Administrator permissions".bold()
@@ -5835,7 +5828,7 @@ impl ChatWidget {
                 name: "Quit".to_string(),
                 description: None,
                 actions: vec![Box::new(move |tx| {
-                    quit_otel.counter("codex.windows_sandbox.fallback_stay_current", 1, &[]);
+                    quit_otel.counter("codex.windows_sandbox.fallback_prompt_quit", 1, &[]);
                     tx.send(AppEvent::Exit(ExitMode::ShutdownFirst));
                 })],
                 dismiss_on_select: true,
@@ -5853,12 +5846,7 @@ impl ChatWidget {
     }
 
     #[cfg(not(target_os = "windows"))]
-    pub(crate) fn open_windows_sandbox_fallback_prompt(
-        &mut self,
-        _preset: ApprovalPreset,
-        _reason: WindowsSandboxFallbackReason,
-    ) {
-    }
+    pub(crate) fn open_windows_sandbox_fallback_prompt(&mut self, _preset: ApprovalPreset) {}
 
     #[cfg(target_os = "windows")]
     pub(crate) fn maybe_prompt_windows_sandbox_enable(&mut self, show_now: bool) {