diff --git a/src/dlangui/graphics/gldrawbuf.d b/src/dlangui/graphics/gldrawbuf.d
index 2eb772b5..71df709a 100644
--- a/src/dlangui/graphics/gldrawbuf.d
+++ b/src/dlangui/graphics/gldrawbuf.d
@@ -344,7 +344,7 @@ private abstract class GLCache
                 if (!_texture.ID)
                     return;
             }
-            Log.d("updateTexture for cache page - setting image ", _drawbuf.width, "x", _drawbuf.height, " tx=", _texture.ID);
+            Log.d("updateTexture for cache page - setting image ", _drawbuf.width, "x", _drawbuf.height, " tx=", _texture ? _texture.ID : 0);
             uint * pixels = _drawbuf.scanLine(0);
             if (!glSupport.setTextureImage(_texture, _drawbuf.width, _drawbuf.height, cast(ubyte*)pixels)) {
                 destroy(_texture);
@@ -527,7 +527,7 @@ private class GLImageCache : GLCache
         void drawItem(GLCacheItem item, Rect dstrc, Rect srcrc, uint color, uint options, Rect * clip, int rotationAngle) {
             if (_needUpdateTexture)
                 updateTexture();
-            if (_texture.ID != 0) {
+            if (_texture && _texture.ID != 0) {
                 //rotationAngle = 0;
                 int rx = dstrc.middlex;
                 int ry = dstrc.middley;
@@ -628,7 +628,7 @@ private class GLGlyphCache : GLCache
         void drawItem(GLCacheItem item, Rect dstrc, Rect srcrc, uint color, Rect * clip) {
             if (_needUpdateTexture)
                 updateTexture();
-            if (_texture.ID != 0) {
+            if (_texture && _texture.ID != 0) {
                 // convert coordinates to cached texture
                 srcrc.offset(item._rc.left, item._rc.top);
                 if (clip) {
diff --git a/src/dlangui/platforms/windows/winapp.d b/src/dlangui/platforms/windows/winapp.d
index 81fbc9ff..964a5cec 100644
--- a/src/dlangui/platforms/windows/winapp.d
+++ b/src/dlangui/platforms/windows/winapp.d
@@ -167,8 +167,15 @@ static if (ENABLE_OPENGL) {
         bool _error;
         /// Init OpenGL context, if not yet initialized
         bool init(HDC hDC) {
-            if (_hGLRC)
+            if (_hGLRC) {
+                // just setup pixel format
+                if (setupPixelFormat(hDC)) {
+                    Log.i("OpenGL context already exists. Setting pixel format.");
+                } else {
+                    Log.e("Cannot setup pixel format");
+                }
                 return true;
+            }
             if (_error)
                 return false;
             if (setupPixelFormat(hDC)) {
@@ -203,11 +210,15 @@ static if (ENABLE_OPENGL) {
         }
         /// make this context current for DC
         void bind(HDC hDC) {
-            wglMakeCurrent(hDC, _hGLRC);
+            if (!wglMakeCurrent(hDC, _hGLRC)) {
+                import std.string : format;
+                Log.e("wglMakeCurrent is failed. GetLastError=%x".format(GetLastError()));
+            }
         }
         /// make null context current for DC
         void unbind(HDC hDC) {
-            wglMakeCurrent(hDC, null);
+            //wglMakeCurrent(hDC, null);
+            wglMakeCurrent(null, null);
         }
         void swapBuffers(HDC hDC) {
             SwapBuffers(hDC);
@@ -312,7 +323,7 @@ class Win32Window : Window {
             }
             buf.afterDrawing();
             sharedGLContext.swapBuffers(hdc);
-            sharedGLContext.unbind(hdc);
+            //sharedGLContext.unbind(hdc);
             destroy(buf);
         }
     }