diff --git a/QRCoder/PngByteQRCode.cs b/QRCoder/PngByteQRCode.cs
index 43045b1f..106cc55b 100644
--- a/QRCoder/PngByteQRCode.cs
+++ b/QRCoder/PngByteQRCode.cs
@@ -261,12 +261,7 @@ public void WriteScanlines(byte[] scanlines)
             _stream.WriteByte(0x9C); // Check bits.
 
             // Compressed data.
-            idatStream.Position = 0;
-#if NET35
             idatStream.WriteTo(_stream);
-#else
-            idatStream.CopyTo(_stream);
-#endif
             // Deflate checksum.
             var adler = Adler32(scanlines, 0, scanlines.Length);
             WriteIntBigEndian(adler);