diff --git a/apps/web/src/components/sidebar/updateEverything.logic.test.ts b/apps/web/src/components/sidebar/updateEverything.logic.test.ts
index 58328dbc1eeeb..75f537f6727be 100644
--- a/apps/web/src/components/sidebar/updateEverything.logic.test.ts
+++ b/apps/web/src/components/sidebar/updateEverything.logic.test.ts
@@ -45,6 +45,20 @@ function machine(
   };
 }
 
+// A desktop-mode server the desktop app cannot control, such as a WSL backend or an older app.
+function withoutDesktopControl(base: UpdateEverythingMachine): UpdateEverythingMachine {
+  return {
+    ...base,
+    serverConfig: {
+      ...base.serverConfig!,
+      environment: {
+        ...base.serverConfig!.environment,
+        capabilities: { repositoryIdentity: true, serverSelfUpdate: "desktop-managed" },
+      },
+    },
+  };
+}
+
 describe("collectServerUpdateTargets", () => {
   it("updates remote servers that can move to the target and names every skipped one", () => {
     const { targets, skipped } = collectServerUpdateTargets(
@@ -67,6 +81,7 @@ describe("collectServerUpdateTargets", () => {
         machine("current", "0.0.50", "boot-service"),
         machine("current-offline", "0.0.50", "boot-service", { connected: false }),
         machine("manual", "0.0.40", undefined),
+        withoutDesktopControl(machine("wsl-backend", "0.0.40", "desktop-managed")),
       ],
       "0.0.50",
     );
@@ -82,6 +97,7 @@ describe("collectServerUpdateTargets", () => {
       ["no-scope", "no permission"],
       ["busy", "already updating"],
       ["manual", "needs a manual update"],
+      ["wsl-backend", "update T3 Code on that machine"],
     ]);
   });
 
@@ -215,15 +231,9 @@ describe("collectChannelSwitchTargets", () => {
         host(machine("service", "0.1.2", "boot-service"), 70),
         // A Stable tag built a migration the latest Nightly does not have yet.
         host(machine("ahead", "0.1.3", "boot-service"), 73),
-        machine("old-desktop", "0.1.2", "desktop-managed", {
-          serverConfig: {
-            ...machine("old-desktop", "0.1.2", "desktop-managed").serverConfig!,
-            environment: {
-              ...machine("old-desktop", "0.1.2", "desktop-managed").serverConfig!.environment,
-              capabilities: { repositoryIdentity: true, serverSelfUpdate: "desktop-managed" },
-            },
-          },
-        }),
+        withoutDesktopControl(machine("old-desktop", "0.1.2", "desktop-managed")),
+        // Already on Nightly, so it needs an update rather than a channel switch.
+        withoutDesktopControl(machine("behind-desktop", OLD_NIGHTLY, "desktop-managed")),
         machine("current", NIGHTLY, "boot-service"),
         // The server refuses a track its policy rules out, so the dialog skips it up front.
         managedHost(host(machine("no-nightly", "0.1.2", "boot-service"), 70)),
@@ -239,7 +249,8 @@ describe("collectChannelSwitchTargets", () => {
         "ahead",
         `its database has changes ${NIGHTLY} does not support yet; stay on Stable until Nightly has them`,
       ],
-      ["old-desktop", "needs a newer desktop app"],
+      ["old-desktop", "change the update track on that machine"],
+      ["behind-desktop", "update T3 Code on that machine"],
       [
         "no-nightly",
         "Example Corp manages T3 Code updates. Only stable releases can be installed.",
diff --git a/apps/web/src/components/sidebar/updateEverything.logic.ts b/apps/web/src/components/sidebar/updateEverything.logic.ts
index cbbd3baa7c776..818ec4d35f49a 100644
--- a/apps/web/src/components/sidebar/updateEverything.logic.ts
+++ b/apps/web/src/components/sidebar/updateEverything.logic.ts
@@ -66,6 +66,10 @@ export interface SkippedMachine {
   readonly reason: string;
 }
 
+// Desktop servers without the desktop control fd (older apps, WSL backends: wsl.exe cannot pass
+// fds) cannot be updated from here, and their desktop app is not necessarily the stale part.
+const UPDATE_ON_THAT_MACHINE = "update T3 Code on that machine";
+
 /** Skip current and app-hosted servers; the latter update with the app and would relaunch mid-run.
  * Desktop-managed servers use their own feed. Each server's updater checks that it can install the
  * release before it restarts, so no registry precheck runs here. */
@@ -109,7 +113,7 @@ export function collectServerUpdateTargets(
       continue;
     }
     if (selfUpdate === "desktop-managed" && !desktopAppUpdate) {
-      skip("needs a newer desktop app");
+      skip(UPDATE_ON_THAT_MACHINE);
       continue;
     }
     const serverVersion = config.environment.serverVersion;
@@ -336,7 +340,7 @@ function trackSwitchMove(
   if (selfUpdate === null) return { skip: "needs a manual update" };
   if (selfUpdate !== "desktop-managed") return { selfUpdate };
   if (config.environment.capabilities.desktopAppChannelSwitch !== true) {
-    return { skip: "needs a newer desktop app" };
+    return { skip: sameTrack ? UPDATE_ON_THAT_MACHINE : "change the update track on that machine" };
   }
   // Squirrel.Mac renames the bundle for the new track and then cannot relaunch it.
   if (!sameTrack && config.environment.platform.os === "darwin") {