diff --git a/window_scene/screen_session_manager/src/screen_session_manager.cpp b/window_scene/screen_session_manager/src/screen_session_manager.cpp
index 7bfa8bdbe7a50debda335fca622f572641e4fd03..3ee1731b67eefa5eaa74f023e709c6d0af200df8 100644
--- a/window_scene/screen_session_manager/src/screen_session_manager.cpp
+++ b/window_scene/screen_session_manager/src/screen_session_manager.cpp
@@ -8276,15 +8276,15 @@ void ScreenSessionManager::NotifyClientProxyUpdateFoldDisplayMode(FoldDisplayMod
 void ScreenSessionManager::ScbClientDeathCallback(int32_t deathScbPid)
 {
     std::unique_lock<std::mutex> lock(oldScbPidsMutex_);
-    if (deathScbPid == currentScbPId_ || currentScbPId_ == INVALID_SCB_PID) {
-        SetClientProxy(nullptr);
-        TLOGE(WmsLogTag::DMS, "death callback and set clientProxy null");
-    }
     if (scbSwitchCV_.wait_for(lock, std::chrono::milliseconds(CV_WAIT_SCBSWITCH_MS))
         == std::cv_status::timeout) {
         TLOGE(WmsLogTag::DMS, "set client task deathScbPid:%{public}d, timeout: %{public}d",
             deathScbPid, CV_WAIT_SCBSWITCH_MS);
     }
+    if (deathScbPid == currentScbPId_ || currentScbPId_ == INVALID_SCB_PID) {
+        SetClientProxy(nullptr);
+        TLOGE(WmsLogTag::DMS, "death callback and set clientProxy null");
+    }
     std::ostringstream oss;
     oss << "Scb client death: " << deathScbPid;
     TLOGI(WmsLogTag::DMS, "%{public}s", oss.str().c_str());
@@ -8316,6 +8316,7 @@ void ScreenSessionManager::SwitchUser()
         return;
     }
     auto userId = GetUserIdByCallingUid();
+    auto newScbPid = IPCSkeleton::GetCallingPid();
     currentUserIdForSettings_ = userId;
     if (g_isPcDevice && userSwitching_) {
         std::unique_lock<std::mutex> lock(switchUserMutex_);
@@ -8324,10 +8325,7 @@ void ScreenSessionManager::SwitchUser()
             userSwitching_ = false;
         }
     }
-    {
-        std::lock_guard<std::mutex> lock(oldScbPidsMutex_);
-        SwitchScbNodeHandle(userId, IPCSkeleton::GetCallingPid(), false);
-    }
+    SwitchScbNodeHandle(userId, newScbPid, false);
     MockSessionManagerService::GetInstance().NotifyWMSConnected(userId, GetDefaultScreenId(), false);
 #endif
 }
@@ -8581,23 +8579,21 @@ void ScreenSessionManager::SetClient(const sptr<IScreenSessionManagerClient>& cl
             userSwitching_ = false;
         }
     }
-    {
-        std::unique_lock<std::mutex> lock(oldScbPidsMutex_);
-        SetClientProxy(client);
-        auto userId = GetUserIdByCallingUid();
-        auto newScbPid = IPCSkeleton::GetCallingPid();
+    SetClientProxy(client);
+    auto userId = GetUserIdByCallingUid();
+    auto newScbPid = IPCSkeleton::GetCallingPid();
 
-        std::ostringstream oss;
-        oss << "set client userId: " << userId << " clientName: " << SysCapUtil::GetClientName();
-        TLOGI(WmsLogTag::DMS, "%{public}s", oss.str().c_str());
-        screenEventTracker_.RecordEvent(oss.str());
-        currentUserIdForSettings_ = userId;
-        MockSessionManagerService::GetInstance().NotifyWMSConnected(userId, GetDefaultScreenId(), true);
-        NotifyClientProxyUpdateFoldDisplayMode(GetFoldDisplayMode());
-        SetClientInner();
-        SwitchScbNodeHandle(userId, newScbPid, true);
-    }
-    AddScbClientDeathRecipient(client, IPCSkeleton::GetCallingPid());
+    std::ostringstream oss;
+    oss << "set client userId: " << userId << " clientName: " << SysCapUtil::GetClientName();
+    TLOGI(WmsLogTag::DMS, "%{public}s", oss.str().c_str());
+    screenEventTracker_.RecordEvent(oss.str());
+    currentUserIdForSettings_ = userId;
+    MockSessionManagerService::GetInstance().NotifyWMSConnected(userId, GetDefaultScreenId(), true);
+    NotifyClientProxyUpdateFoldDisplayMode(GetFoldDisplayMode());
+    SetClientInner();
+    SwitchScbNodeHandle(userId, newScbPid, true);
+
+    AddScbClientDeathRecipient(client, newScbPid);
 
     static bool isNeedSwitchScreen = FoldScreenStateInternel::IsSingleDisplayPocketFoldDevice() ||
         FoldScreenStateInternel::IsSingleDisplayFoldDevice();
@@ -8625,6 +8621,7 @@ void ScreenSessionManager::SwitchScbNodeHandle(int32_t newUserId, int32_t newScb
     TLOGI(WmsLogTag::DMS, "%{public}s", oss.str().c_str());
     screenEventTracker_.RecordEvent(oss.str());
 
+    std::unique_lock<std::mutex> lock(oldScbPidsMutex_);
     if (currentScbPId_ != INVALID_SCB_PID) {
         auto pidIter = std::find(oldScbPids_.begin(), oldScbPids_.end(), currentScbPId_);
         if (pidIter == oldScbPids_.end() && currentScbPId_ > 0) {