diff --git a/reactos/dll/win32/user32/windows/message.c b/reactos/dll/win32/user32/windows/message.c
index 276077788a7..51bfa418556 100644
--- a/reactos/dll/win32/user32/windows/message.c
+++ b/reactos/dll/win32/user32/windows/message.c
@@ -414,9 +414,44 @@ MsgiAnsiToUnicodeMessage(LPMSG UnicodeMsg, LPMSG AnsiMsg)
     case LB_ADDFILE:
     case EM_REPLACESEL:
       {
-        UNICODE_STRING UnicodeString;
-        RtlCreateUnicodeStringFromAsciiz(&UnicodeString, (LPSTR)AnsiMsg->lParam);
-        UnicodeMsg->lParam = (LPARAM)UnicodeString.Buffer;
+        goto ConvertLParamString;
+      }
+
+    case LB_ADDSTRING:
+    case LB_ADDSTRING_LOWER:
+    case LB_ADDSTRING_UPPER:
+    case LB_INSERTSTRING:
+    case LB_INSERTSTRING_UPPER:
+    case LB_INSERTSTRING_LOWER:
+    case LB_FINDSTRING:
+    case LB_FINDSTRINGEXACT:
+    case LB_SELECTSTRING:
+      {
+        DWORD dwStyle = GetWindowLongW(AnsiMsg->hwnd, GWL_STYLE);
+        if (!(dwStyle & (LBS_OWNERDRAWFIXED | LBS_OWNERDRAWVARIABLE)) &&
+            (dwStyle & LBS_HASSTRINGS))
+          {
+            goto ConvertLParamString;
+          }
+        break;
+      }
+
+    case CB_ADDSTRING:
+    case CB_INSERTSTRING:
+    case CB_FINDSTRING:
+    case CB_FINDSTRINGEXACT:
+    case CB_SELECTSTRING:
+      {
+        DWORD dwStyle = GetWindowLongW(AnsiMsg->hwnd, GWL_STYLE);
+        if (!(dwStyle & (CBS_OWNERDRAWFIXED | CBS_OWNERDRAWVARIABLE)) &&
+            (dwStyle & CBS_HASSTRINGS))
+          {
+            UNICODE_STRING UnicodeString;
+
+ConvertLParamString:
+            RtlCreateUnicodeStringFromAsciiz(&UnicodeString, (LPSTR)AnsiMsg->lParam);
+            UnicodeMsg->lParam = (LPARAM)UnicodeString.Buffer;
+          }
         break;
       }
 
@@ -501,12 +536,48 @@ MsgiAnsiToUnicodeCleanup(LPMSG UnicodeMsg, LPMSG AnsiMsg)
     case LB_ADDFILE:
     case EM_REPLACESEL:
       {
-        UNICODE_STRING UnicodeString;
-        RtlInitUnicodeString(&UnicodeString, (PCWSTR)UnicodeMsg->lParam);
-        RtlFreeUnicodeString(&UnicodeString);
+        goto FreeLParamString;
+      }
+
+    case LB_ADDSTRING:
+    case LB_ADDSTRING_LOWER:
+    case LB_ADDSTRING_UPPER:
+    case LB_INSERTSTRING:
+    case LB_INSERTSTRING_UPPER:
+    case LB_INSERTSTRING_LOWER:
+    case LB_FINDSTRING:
+    case LB_FINDSTRINGEXACT:
+    case LB_SELECTSTRING:
+      {
+        DWORD dwStyle = GetWindowLongW(AnsiMsg->hwnd, GWL_STYLE);
+        if (!(dwStyle & (LBS_OWNERDRAWFIXED | LBS_OWNERDRAWVARIABLE)) &&
+            (dwStyle & LBS_HASSTRINGS))
+          {
+            goto FreeLParamString;
+          }
         break;
       }
 
+    case CB_ADDSTRING:
+    case CB_INSERTSTRING:
+    case CB_FINDSTRING:
+    case CB_FINDSTRINGEXACT:
+    case CB_SELECTSTRING:
+      {
+        DWORD dwStyle = GetWindowLongW(AnsiMsg->hwnd, GWL_STYLE);
+        if (!(dwStyle & (CBS_OWNERDRAWFIXED | CBS_OWNERDRAWVARIABLE)) &&
+            (dwStyle & CBS_HASSTRINGS))
+          {
+            UNICODE_STRING UnicodeString;
+
+FreeLParamString:
+            RtlInitUnicodeString(&UnicodeString, (PCWSTR)UnicodeMsg->lParam);
+            RtlFreeUnicodeString(&UnicodeString);
+          }
+        break;
+      }
+
+
     case WM_NCCREATE:
     case WM_CREATE:
       {
@@ -640,20 +711,58 @@ MsgiUnicodeToAnsiMessage(LPMSG AnsiMsg, LPMSG UnicodeMsg)
           break;
         }
       case WM_SETTEXT:
+      case CB_DIR:
+      case LB_DIR:
+      case LB_ADDFILE:
         {
-          ANSI_STRING AnsiString;
-          UNICODE_STRING UnicodeString;
-          RtlInitUnicodeString(&UnicodeString, (PWSTR) UnicodeMsg->lParam);
-          if (! NT_SUCCESS(RtlUnicodeStringToAnsiString(&AnsiString,
-                                                        &UnicodeString,
-                                                        TRUE)))
-            {
-              return FALSE;
-            }
-          AnsiMsg->lParam = (LPARAM) AnsiString.Buffer;
-          break;
+          goto ConvertLParamString;
 	}
-    }
+
+      case LB_ADDSTRING:
+      case LB_ADDSTRING_LOWER:
+      case LB_ADDSTRING_UPPER:
+      case LB_INSERTSTRING:
+      case LB_INSERTSTRING_UPPER:
+      case LB_INSERTSTRING_LOWER:
+      case LB_FINDSTRING:
+      case LB_FINDSTRINGEXACT:
+      case LB_SELECTSTRING:
+        {
+          DWORD dwStyle = GetWindowLongW(AnsiMsg->hwnd, GWL_STYLE);
+          if (!(dwStyle & (LBS_OWNERDRAWFIXED | LBS_OWNERDRAWVARIABLE)) &&
+              (dwStyle & LBS_HASSTRINGS))
+            {
+              goto ConvertLParamString;
+            }
+          break;
+        }
+
+      case CB_ADDSTRING:
+      case CB_INSERTSTRING:
+      case CB_FINDSTRING:
+      case CB_FINDSTRINGEXACT:
+      case CB_SELECTSTRING:
+        {
+          DWORD dwStyle = GetWindowLongW(AnsiMsg->hwnd, GWL_STYLE);
+          if (!(dwStyle & (CBS_OWNERDRAWFIXED | CBS_OWNERDRAWVARIABLE)) &&
+               (dwStyle & CBS_HASSTRINGS))
+            {
+              ANSI_STRING AnsiString;
+              UNICODE_STRING UnicodeString;
+
+ConvertLParamString:
+              RtlInitUnicodeString(&UnicodeString, (PWSTR) UnicodeMsg->lParam);
+              if (! NT_SUCCESS(RtlUnicodeStringToAnsiString(&AnsiString,
+                                                            &UnicodeString,
+                                                            TRUE)))
+                {
+                  return FALSE;
+                }
+              AnsiMsg->lParam = (LPARAM) AnsiString.Buffer;
+            }
+          break;
+        }
+      }
 
   return TRUE;
 }
@@ -671,10 +780,7 @@ MsgiUnicodeToAnsiCleanup(LPMSG AnsiMsg, LPMSG UnicodeMsg)
         }
       case WM_SETTEXT:
         {
-          ANSI_STRING AString;
-          RtlInitAnsiString(&AString, (PSTR) AnsiMsg->lParam);
-          RtlFreeAnsiString(&AString);
-          break;
+          goto FreeLParamString;
         }
       case WM_CREATE:
       case WM_NCCREATE:
@@ -693,6 +799,45 @@ MsgiUnicodeToAnsiCleanup(LPMSG AnsiMsg, LPMSG UnicodeMsg)
           RtlFreeHeap(GetProcessHeap(), 0, Cs);
           break;
         }
+
+      case LB_ADDSTRING:
+      case LB_ADDSTRING_LOWER:
+      case LB_ADDSTRING_UPPER:
+      case LB_INSERTSTRING:
+      case LB_INSERTSTRING_UPPER:
+      case LB_INSERTSTRING_LOWER:
+      case LB_FINDSTRING:
+      case LB_FINDSTRINGEXACT:
+      case LB_SELECTSTRING:
+        {
+          DWORD dwStyle = GetWindowLongW(AnsiMsg->hwnd, GWL_STYLE);
+          if (!(dwStyle & (LBS_OWNERDRAWFIXED | LBS_OWNERDRAWVARIABLE)) &&
+              (dwStyle & LBS_HASSTRINGS))
+            {
+              goto FreeLParamString;
+            }
+          break;
+        }
+
+      case CB_ADDSTRING:
+      case CB_INSERTSTRING:
+      case CB_FINDSTRING:
+      case CB_FINDSTRINGEXACT:
+      case CB_SELECTSTRING:
+        {
+          DWORD dwStyle = GetWindowLongW(AnsiMsg->hwnd, GWL_STYLE);
+          if (!(dwStyle & (CBS_OWNERDRAWFIXED | CBS_OWNERDRAWVARIABLE)) &&
+               (dwStyle & CBS_HASSTRINGS))
+            {
+              ANSI_STRING AString;
+
+FreeLParamString:
+              RtlInitAnsiString(&AString, (PSTR) AnsiMsg->lParam);
+              RtlFreeAnsiString(&AString);
+            }
+          break;
+        }
+
     }
 
   return TRUE;
diff --git a/reactos/subsystems/win32/win32k/ntuser/message.c b/reactos/subsystems/win32/win32k/ntuser/message.c
index b6005ca0e63..902861ec686 100644
--- a/reactos/subsystems/win32/win32k/ntuser/message.c
+++ b/reactos/subsystems/win32/win32k/ntuser/message.c
@@ -379,11 +379,15 @@ NtUserDispatchMessage(PNTUSERDISPATCHMESSAGEINFO UnsafeMsgInfo)
             MsgInfo.HandledByKernel = FALSE;
             Result = 0;
 
-            MsgInfo.Ansi = !Window->Unicode;
             if (Window->IsSystem)
-                MsgInfo.Proc = (Window->Unicode ? Window->WndProc : Window->WndProcExtra);
+            {
+                MsgInfo.Proc = (!MsgInfo.Ansi ? Window->WndProc : Window->WndProcExtra);
+            }
             else
+            {
+                MsgInfo.Ansi = !Window->Unicode;
                 MsgInfo.Proc = Window->WndProc;
+            }
          }
       }
    }
@@ -1565,11 +1569,15 @@ co_IntDoSendMessage(HWND hWnd,
          Info.Ansi = ! Window->Unicode;
       }
 
-      Info.Ansi = !Window->Unicode;
       if (Window->IsSystem)
-          Info.Proc = (Window->Unicode ? Window->WndProc : Window->WndProcExtra);
+      {
+          Info.Proc = (!Info.Ansi ? Window->WndProc : Window->WndProcExtra);
+      }
       else
+      {
+          Info.Ansi = !Window->Unicode;
           Info.Proc = Window->WndProc;
+      }
    }
    else
    {