diff --git a/server/channels/app/remote_cluster_test.go b/server/channels/app/remote_cluster_test.go
index 2ea1b56fe5c..f4b5ec604dd 100644
--- a/server/channels/app/remote_cluster_test.go
+++ b/server/channels/app/remote_cluster_test.go
@@ -4,11 +4,13 @@
 package app
 
 import (
+	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/require"
 
 	"github.com/mattermost/mattermost/server/public/model"
+	"github.com/mattermost/mattermost/server/v8/channels/testlib"
 )
 
 func setupRemoteCluster(tb testing.TB) *TestHelper {
@@ -18,6 +20,57 @@ func setupRemoteCluster(tb testing.TB) *TestHelper {
 	})
 }
 
+// TestSharedChannelServicesAvailableBeforePluginActivation guards the fix for
+// MM-68622. Plugins that call shared channels APIs from OnActivate previously
+// failed with "Shared Channels Service is disabled" because
+// startInterClusterServices ran after Channels().Start() initialized plugins.
+// Server.Start now starts the inter-cluster services first, so the services
+// must be available by the time plugin initialization begins.
+func TestSharedChannelServicesAvailableBeforePluginActivation(t *testing.T) {
+	mainHelper.Parallel(t)
+	th := setupRemoteCluster(t).InitBasic(t)
+
+	require.NotNil(t, th.Server.GetRemoteClusterService(),
+		"remote cluster service must be initialized after Server.Start")
+	require.NotNil(t, th.Server.GetSharedChannelSyncService(),
+		"shared channel sync service must be initialized after Server.Start")
+
+	// Order check: scs.resume() logs "Shared Channel Service active" from
+	// scs.Start(), and initPlugins logs "Starting up plugins" from
+	// Channels().Start(). The first must precede the second, otherwise plugin
+	// OnActivate would observe a nil service.
+	require.NoError(t, th.TestLogger.Flush())
+	entries := testlib.ParseLogEntries(t, strings.NewReader(th.LogBuffer.String()))
+
+	scsActiveIdx, pluginInitIdx := -1, -1
+	for i, e := range entries {
+		if scsActiveIdx == -1 && e.Msg == "Shared Channel Service active" {
+			scsActiveIdx = i
+		}
+		if pluginInitIdx == -1 && e.Msg == "Starting up plugins" {
+			pluginInitIdx = i
+		}
+	}
+	require.NotEqual(t, -1, scsActiveIdx,
+		"expected log message 'Shared Channel Service active' from scs.resume()")
+	require.NotEqual(t, -1, pluginInitIdx,
+		"expected log message 'Starting up plugins' from initPlugins")
+	require.Less(t, scsActiveIdx, pluginInitIdx,
+		"shared channel service must activate before plugin initialization (MM-68622)")
+
+	// Plugin entry path: this is the App-layer call a plugin would make from
+	// OnActivate. Before MM-68622 it would return "Shared Channels Service is
+	// disabled" because GetSharedChannelSyncService() was still nil.
+	pluginID := "com.test.startup-" + model.NewId()
+	_, err := th.App.RegisterPluginForSharedChannels(th.Context, model.RegisterPluginOpts{
+		Displayname: "startup test plugin",
+		PluginID:    pluginID,
+		CreatorID:   th.BasicUser.Id,
+	})
+	require.NoError(t, err,
+		"RegisterPluginForSharedChannels must succeed when shared channels is enabled")
+}
+
 func TestAddRemoteCluster(t *testing.T) {
 	mainHelper.Parallel(t)
 	th := setupRemoteCluster(t).InitBasic(t)
diff --git a/server/channels/app/server.go b/server/channels/app/server.go
index c81dd89bb37..547c5448251 100644
--- a/server/channels/app/server.go
+++ b/server/channels/app/server.go
@@ -856,6 +856,12 @@ func stripPort(hostport string) string {
 }
 
 func (s *Server) Start() error {
+	// Start inter-cluster services first so shared channels APIs are
+	// available when plugins activate during channels startup.
+	if err := s.startInterClusterServices(s.License()); err != nil {
+		mlog.Error("Error starting inter-cluster services", mlog.Err(err))
+	}
+
 	// Start channels.
 	// This needs to happen before because channels is dependent on the HTTP server.
 	if err := s.Channels().Start(); err != nil {
@@ -1113,10 +1119,6 @@ func (s *Server) Start() error {
 		}
 	}
 
-	if err := s.startInterClusterServices(s.License()); err != nil {
-		mlog.Error("Error starting inter-cluster services", mlog.Err(err))
-	}
-
 	return nil
 }