diff --git a/NucleicRemote/NucleicRemote/Models/RemoteStore.swift b/NucleicRemote/NucleicRemote/Models/RemoteStore.swift
index 91d286f..ead295a 100644
--- a/NucleicRemote/NucleicRemote/Models/RemoteStore.swift
+++ b/NucleicRemote/NucleicRemote/Models/RemoteStore.swift
@@ -783,6 +783,15 @@ final class RemoteStore: ObservableObject {
             openDiff = diff
             diffLoading = false
         case .wireError(let error):
+            // A channel mismatch is a permanent, connection-fatal condition (the host and this
+            // remote were built from incompatible release channels). Surface it as a persistent
+            // failure with a clear message rather than a transient bubble that the follow-on
+            // `.closed` would paper over with "reconnecting".
+            if error.code == .channelMismatch {
+                teardown()
+                connectivity = .failed(error.message)
+                break
+            }
             // Not fatal — surface as a transient bubble (the Mac's last-error overlay).
             // Losing an approval race isn't an error worth interrupting for; the card
             // collapses on the matching `approvalResolved`.