diff --git a/dlls/windowscodecs/info.c b/dlls/windowscodecs/info.c
index a89759bd2a9..64c3855e4e0 100644
--- a/dlls/windowscodecs/info.c
+++ b/dlls/windowscodecs/info.c
@@ -1064,6 +1064,7 @@ HRESULT WINAPI WICConvertBitmapSource(REFWICPixelFormatGUID dstFormat, IWICBitma
     }
     else
     {
+        FIXME("cannot convert %s to %s\n", debugstr_guid(&srcFormat), debugstr_guid(dstFormat));
         *ppIDst = NULL;
         return WINCODEC_ERR_COMPONENTNOTFOUND;
     }