diff --git a/Sources/Shotdeck/SettingsView.swift b/Sources/Shotdeck/SettingsView.swift
index 5291120..9c8ba42 100644
--- a/Sources/Shotdeck/SettingsView.swift
+++ b/Sources/Shotdeck/SettingsView.swift
@@ -82,21 +82,20 @@ struct SettingsView: View {
                             model.chooseOneDriveFolder()
                         }
                     } else {
-                        HStack(spacing: 8) {
-                            Text("No OneDrive folder found — sign in to OneDrive or choose a folder.")
-                                .font(.caption)
-                                .foregroundStyle(.secondary)
-                                .fixedSize(horizontal: false, vertical: true)
-                                .frame(maxWidth: .infinity, alignment: .leading)
-                            Button("Choose…") { model.chooseOneDriveFolder() }
+                        // One-line row, same shape as the normal path row: "Not found"
+                        // where the path would be, Choose… stays live. The explanation
+                        // moves to the caption below instead of wrapping this row.
+                        folderValue(path: "Not found") {
+                            model.chooseOneDriveFolder()
                         }
-                        .frame(minHeight: 22)
                     }
                 }
 
                 GridRow {
                     Text(
-                        "The PDF is saved here and this same folder is watched for the marked-up copy. On the iPad open it from Files > OneDrive."
+                        model.resolvedOneDriveFolder != nil
+                            ? "The PDF is saved here and this same folder is watched for the marked-up copy. On the iPad open it from Files > OneDrive."
+                            : "No OneDrive folder found. Sign in to OneDrive, or choose a folder."
                     )
                     .font(.caption)
                     .foregroundStyle(.secondary)
@@ -249,7 +248,18 @@ extension AppModel: SettingsWindowPresenting {
     /// doesn't exist yet, and re-points the running watcher (folder + recordUncommented)
     /// at the new state. Switching back to AirDrop restores its own stored overrides
     /// untouched, since AirDrop and OneDrive folder settings are stored under separate keys.
+    /// Refuses while a send is in flight (send() snapshots its own folder/transport, but
+    /// switching mid-send is still confusing UX — nothing to gain by allowing it).
+    /// The async reconcile below is generation-guarded: `reconcileGeneration` is bumped
+    /// synchronously before the Task starts, and the Task checks its own snapshot against
+    /// the live value before every mutating step, so rapid toggling (this function or
+    /// chooseOneDriveFolder, in any order) always lets the LAST choice win instead of an
+    /// earlier, superseded call applying its stale folder/flag after a later one already won.
     func chooseTransport(_ value: SendTransport) {
+        guard !isSending else {
+            setStatus("Finish the current send first.")
+            return
+        }
         guard value != transport else { return }
         TransportSettings.setTransport(value)
         setTransport(value)
@@ -261,11 +271,17 @@ extension AppModel: SettingsWindowPresenting {
         }
         setFolderURLs(outbox: folders.outbox, watch: folders.watch)
         setResolvedOneDriveFolder(OneDriveLocator.resolveOneDriveFolder())
+
+        reconcileGeneration += 1
+        let generation = reconcileGeneration
         Task {
+            guard generation == self.reconcileGeneration else { return }
             await watcher.setRecordUncommented(value == .airDrop)
+            guard generation == self.reconcileGeneration else { return }
             do {
                 try await watcher.updateWatchFolder(folders.watch)
             } catch {
+                guard generation == self.reconcileGeneration else { return }
                 setStatus(
                     (error as? ShotdeckError)?.errorDescription ?? "Could not switch the watch folder."
                 )
@@ -273,7 +289,13 @@ extension AppModel: SettingsWindowPresenting {
         }
     }
 
+    /// Refuses while a send is in flight, same reasoning as chooseTransport. See
+    /// chooseTransport's doc comment for the generation-guard mechanism shared here.
     func chooseOneDriveFolder() {
+        guard !isSending else {
+            setStatus("Finish the current send first.")
+            return
+        }
         let start = resolvedOneDriveFolder ?? FileManager.default.homeDirectoryForCurrentUser
         guard let url = chooseDirectory(startingAt: start) else { return }
         TransportSettings.setOneDriveFolder(url)
@@ -281,11 +303,17 @@ extension AppModel: SettingsWindowPresenting {
         setResolvedOneDriveFolder(OneDriveLocator.resolveOneDriveFolder())
         guard transport == .oneDrive else { return }
         setFolderURLs(outbox: url, watch: url)
+
+        reconcileGeneration += 1
+        let generation = reconcileGeneration
         Task {
+            guard generation == self.reconcileGeneration else { return }
             do {
                 try await watcher.updateWatchFolder(url)
+                guard generation == self.reconcileGeneration else { return }
                 setStatus("OneDrive folder set to \(url.lastPathComponent).")
             } catch {
+                guard generation == self.reconcileGeneration else { return }
                 setStatus(
                     (error as? ShotdeckError)?.errorDescription ?? "Could not switch the watch folder."
                 )