diff --git a/include/freerdp/update.h b/include/freerdp/update.h
index 711c9906d..c4c9afe56 100644
--- a/include/freerdp/update.h
+++ b/include/freerdp/update.h
@@ -48,7 +48,10 @@ struct _BITMAP_DATA
 	uint32 bitsPerPixel;
 	uint32 flags;
 	uint32 bitmapLength;
-	uint8 bitmapComprHdr[8];
+	uint32 cbCompFirstRowSize;
+	uint32 cbCompMainBodySize;
+	uint32 cbScanWidth;
+	uint32 cbUncompressedSize;
 	uint8* bitmapDataStream;
 	boolean compressed;
 };
diff --git a/libfreerdp-core/capabilities.c b/libfreerdp-core/capabilities.c
index afe61997a..0b9cac2e5 100644
--- a/libfreerdp-core/capabilities.c
+++ b/libfreerdp-core/capabilities.c
@@ -140,7 +140,7 @@ void rdp_write_general_capability_set(STREAM* s, rdpSettings* settings)
 
 	header = rdp_capability_set_start(s);
 
-	extraFlags = LONG_CREDENTIALS_SUPPORTED; /* | NO_BITMAP_COMPRESSION_HDR; */
+	extraFlags = LONG_CREDENTIALS_SUPPORTED | NO_BITMAP_COMPRESSION_HDR;
 
 	if (settings->auto_reconnection)
 		extraFlags |= AUTORECONNECT_SUPPORTED;
@@ -155,8 +155,8 @@ void rdp_write_general_capability_set(STREAM* s, rdpSettings* settings)
 		settings->suppress_output = false;
 	}
 
-	stream_write_uint16(s, 0); /* osMajorType (2 bytes) */
-	stream_write_uint16(s, 0); /* osMinorType (2 bytes) */
+	stream_write_uint16(s, OSMAJORTYPE_WINDOWS); /* osMajorType (2 bytes) */
+	stream_write_uint16(s, OSMINORTYPE_WINDOWS_NT); /* osMinorType (2 bytes) */
 	stream_write_uint16(s, CAPS_PROTOCOL_VERSION); /* protocolVersion (2 bytes) */
 	stream_write_uint16(s, 0); /* pad2OctetsA (2 bytes) */
 	stream_write_uint16(s, 0); /* generalCompressionTypes (2 bytes) */
diff --git a/libfreerdp-core/capabilities.h b/libfreerdp-core/capabilities.h
index 85460c1fa..5e85e8e79 100644
--- a/libfreerdp-core/capabilities.h
+++ b/libfreerdp-core/capabilities.h
@@ -61,6 +61,22 @@
 
 #define SOURCE_DESCRIPTOR			"MSTSC"
 
+#define OSMAJORTYPE_UNSPECIFIED			0x0000
+#define OSMAJORTYPE_WINDOWS			0x0001
+#define OSMAJORTYPE_OS2				0x0002
+#define OSMAJORTYPE_MACINTOSH			0x0003
+#define OSMAJORTYPE_UNIX			0x0004
+
+#define OSMINORTYPE_UNSPECIFIED			0x0000
+#define OSMINORTYPE_WINDOWS_31X			0x0001
+#define OSMINORTYPE_WINDOWS_95			0x0002
+#define OSMINORTYPE_WINDOWS_NT			0x0003
+#define OSMINORTYPE_OS2_V21			0x0004
+#define OSMINORTYPE_POWER_PC			0x0005
+#define OSMINORTYPE_MACINTOSH			0x0006
+#define OSMINORTYPE_NATIVE_XSERVER		0x0007
+#define OSMINORTYPE_PSEUDO_XSERVER		0x0008
+
 /* Capabilities Protocol Version */
 #define CAPS_PROTOCOL_VERSION			0x0200
 
diff --git a/libfreerdp-core/update.c b/libfreerdp-core/update.c
index 49c4ebf21..458eb646c 100644
--- a/libfreerdp-core/update.c
+++ b/libfreerdp-core/update.c
@@ -61,15 +61,14 @@ void update_read_bitmap_data(STREAM* s, BITMAP_DATA* bitmap_data)
 
 	if (bitmap_data->flags & BITMAP_COMPRESSION)
 	{
-		uint16 cbCompMainBodySize;
-		uint16 cbUncompressedSize;
-
-		stream_seek_uint16(s); /* cbCompFirstRowSize (2 bytes) */
-		stream_read_uint16(s, cbCompMainBodySize); /* cbCompMainBodySize (2 bytes) */
-		stream_seek_uint16(s); /* cbScanWidth (2 bytes) */
-		stream_read_uint16(s, cbUncompressedSize); /* cbUncompressedSize (2 bytes) */
-
-		bitmap_data->bitmapLength = cbCompMainBodySize;
+		if (!(bitmap_data->flags & NO_BITMAP_COMPRESSION_HDR))
+		{
+			stream_read_uint16(s, bitmap_data->cbCompFirstRowSize); /* cbCompFirstRowSize (2 bytes) */
+			stream_read_uint16(s, bitmap_data->cbCompMainBodySize); /* cbCompMainBodySize (2 bytes) */
+			stream_read_uint16(s, bitmap_data->cbScanWidth); /* cbScanWidth (2 bytes) */
+			stream_read_uint16(s, bitmap_data->cbUncompressedSize); /* cbUncompressedSize (2 bytes) */
+			bitmap_data->bitmapLength = bitmap_data->cbCompMainBodySize;
+		}
 
 		bitmap_data->compressed = true;
 		stream_get_mark(s, bitmap_data->bitmapDataStream);