diff --git a/mac/Sources/CodeBurnMenubar/CodeBurnApp.swift b/mac/Sources/CodeBurnMenubar/CodeBurnApp.swift
index dd31cb9..d6c1cd0 100644
--- a/mac/Sources/CodeBurnMenubar/CodeBurnApp.swift
+++ b/mac/Sources/CodeBurnMenubar/CodeBurnApp.swift
@@ -971,7 +971,12 @@ final class AppDelegate: NSObject, NSApplicationDelegate, NSPopoverDelegate {
                 alert.alertStyle = .warning
             } else if updateChecker.updateAvailable, let latest = updateChecker.latestVersion {
                 alert.messageText = "Update Available"
-                alert.informativeText = "\(AppVersion.display(latest)) is available (you have \(AppVersion.display(updateChecker.currentVersion))). Run:\n\ncodeburn menubar --force"
+                let header = "\(AppVersion.display(latest)) is available (you have \(AppVersion.display(updateChecker.currentVersion)))."
+                if updateChecker.cliTooOldForUpdate {
+                    alert.informativeText = "\(header) Your codeburn CLI is too old to install it. First run:\n\n\(updateChecker.cliUpdateCommand)\n\nthen:\n\ncodeburn menubar --force"
+                } else {
+                    alert.informativeText = "\(header) Run:\n\ncodeburn menubar --force"
+                }
                 alert.alertStyle = .informational
             } else {
                 alert.messageText = "Up to Date"
diff --git a/mac/Sources/CodeBurnMenubar/Data/UpdateChecker.swift b/mac/Sources/CodeBurnMenubar/Data/UpdateChecker.swift
index e85dc08..0d87a34 100644
--- a/mac/Sources/CodeBurnMenubar/Data/UpdateChecker.swift
+++ b/mac/Sources/CodeBurnMenubar/Data/UpdateChecker.swift
@@ -8,6 +8,11 @@ private let cachedVersionKey = "UpdateChecker.latestVersion"
 private let cachedCliVersionKey = "UpdateChecker.latestCliVersion"
 private let updateTimeoutSeconds: UInt64 = 120
 private let maxUpdateStderrBytes = 64 * 1024
+// The installer that scans `mac-v*` releases for the menubar zip (instead of
+// `/releases/latest`, which can resolve to a CLI release that carries no menubar
+// asset) landed in CLI 0.9.9 (commit 909efcf). Older CLIs cannot perform a correct
+// `menubar --force`, so we refuse to run them and ask the user to upgrade the CLI first.
+private let minCliVersionForUpdate = "0.9.9"
 
 private final class LockedDataBuffer: @unchecked Sendable {
     private let lock = NSLock()
@@ -51,6 +56,13 @@ final class UpdateChecker {
         return normalizedLatest.compare(normalizedInstalled, options: .numeric) == .orderedDescending
     }
 
+    /// True when the installed CLI predates the `menubar --force` fix and would fail to
+    /// install the new app. Distinct from `cliUpdateAvailable`: a CLI can be behind the
+    /// latest release yet still new enough (>= 0.9.9) to update the menubar correctly.
+    var cliTooOldForUpdate: Bool {
+        Self.isCliTooOld(installed: installedCliVersion)
+    }
+
     var cliUpdateCommand: String {
         let argv = CodeburnCLI.baseArgv()
         let path = argv.first ?? ""
@@ -146,7 +158,19 @@ final class UpdateChecker {
         return nil
     }
 
+    nonisolated static func isCliTooOld(installed: String?) -> Bool {
+        guard let installed else { return false }
+        let normalizedInstalled = AppVersion.normalize(installed)
+        guard !normalizedInstalled.isEmpty else { return false }
+        return AppVersion.normalize(minCliVersionForUpdate).compare(normalizedInstalled, options: .numeric) == .orderedDescending
+    }
+
     func performUpdate() {
+        installedCliVersion = Self.queryInstalledCliVersion()
+        if cliTooOldForUpdate {
+            updateError = "Your codeburn CLI (\(AppVersion.display(installedCliVersion ?? ""))) is too old to update the menubar. Run “\(cliUpdateCommand)” first, then try again."
+            return
+        }
         isUpdating = true
         updateError = nil
 
diff --git a/mac/Tests/CodeBurnMenubarTests/UpdateCheckerTests.swift b/mac/Tests/CodeBurnMenubarTests/UpdateCheckerTests.swift
index 44f52b5..63084d9 100644
--- a/mac/Tests/CodeBurnMenubarTests/UpdateCheckerTests.swift
+++ b/mac/Tests/CodeBurnMenubarTests/UpdateCheckerTests.swift
@@ -36,4 +36,25 @@ struct UpdateCheckerTests {
 
         #expect(UpdateChecker.resolveLatestMenubarRelease(in: releases) == nil)
     }
+
+    @Test("flags CLI older than the menubar-update fix as too old")
+    func flagsCliBelowMinimumAsTooOld() {
+        #expect(UpdateChecker.isCliTooOld(installed: "0.9.8"))
+        #expect(UpdateChecker.isCliTooOld(installed: "v0.9.8"))
+        #expect(UpdateChecker.isCliTooOld(installed: "0.8.12"))
+    }
+
+    @Test("accepts CLI at or above the menubar-update fix version")
+    func acceptsCliAtOrAboveMinimum() {
+        #expect(!UpdateChecker.isCliTooOld(installed: "0.9.9"))
+        #expect(!UpdateChecker.isCliTooOld(installed: "0.9.10"))
+        #expect(!UpdateChecker.isCliTooOld(installed: "0.9.14"))
+        #expect(!UpdateChecker.isCliTooOld(installed: "1.0.0"))
+    }
+
+    @Test("does not flag when the CLI version is unknown")
+    func ignoresUnknownCliVersion() {
+        #expect(!UpdateChecker.isCliTooOld(installed: nil))
+        #expect(!UpdateChecker.isCliTooOld(installed: ""))
+    }
 }