diff --git a/dlls/gdiplus/image.c b/dlls/gdiplus/image.c
index 6b827bac9ca..3ffb7c77a3a 100644
--- a/dlls/gdiplus/image.c
+++ b/dlls/gdiplus/image.c
@@ -226,6 +226,7 @@ GpStatus WINGDIPAPI GdipBitmapUnlockBits(GpBitmap* bitmap,
 
     GdipFree(bitmap->bitmapbits);
     bitmap->bitmapbits = NULL;
+    bitmap->lockmode = 0;
 
     return Ok;
 }
diff --git a/dlls/gdiplus/tests/image.c b/dlls/gdiplus/tests/image.c
index 4047feefe80..d40f6c67424 100644
--- a/dlls/gdiplus/tests/image.c
+++ b/dlls/gdiplus/tests/image.c
@@ -237,10 +237,8 @@ static void test_LockBits(void)
     }
 
     /* write, consecutive */
-    todo_wine {
-        stat = GdipBitmapLockBits(bm, &rect, ImageLockModeWrite, PixelFormat24bppRGB, &bd);
-        expect(Ok, stat);
-    }
+    stat = GdipBitmapLockBits(bm, &rect, ImageLockModeWrite, PixelFormat24bppRGB, &bd);
+    expect(Ok, stat);
 
     if (stat == Ok) {
         stat = GdipBitmapUnlockBits(bm, &bd);