We are leveraging an open source RDP client called FreeRDP (https://github.com/FreeRDP/FreeRDP) to access various Windows Servers. We spun up new instances of Windows Server 2008 R2 SP1 and Windows Server 2012 in Azure. When targeting the Windows Server 2008 machine, the RDP session worked well and text was rendered with glyphs. When targeting the Windows Server 2012 machine, the RDP session worked well but the text was rendered with bitmaps instead.
Examining the Client Confirm Active PDU (http://msdn.microsoft.com/en-us/library/cc240488.aspx) sent during the Capabilities Exchangeof the RDP connection handshake, we confirmed that the Glyph Cache Capability Set (http://msdn.microsoft.com/en-us/library/cc240565.aspx) was set in the capabilitySets field. TheGlyphSupportLevel was set to Glyph_Support_Full. Additionally, the Order Capability Set(http://msdn.microsoft.com/en-us/library/cc240556.aspx) was set in the capabilitySets field of the Client Confirm Active PDU.Both TS_NEG_FAST_GLYPH_INDEX and TS_NEG_INDEX_INDEX were set on theorderSupport field of the Order Capability Set.
Basically the RDP handshake was fine but neither FASTGLYPH_ORDER (http://msdn.microsoft.com/en-us/library/cc241593.aspx) nor GLYPHINDEX_ORDER (http://msdn.microsoft.com/en-us/library/cc241591.aspx) messages were being sent from the server to the client when targeting a Windows Server 2012 machine. Since by default Windows Server 2008 uses RDP 7 and Windows Server 2012 uses RDP 8, could glyph support have been dropped? Is there a way to configure Windows Server 2012 to support glyphs or revert it back to RDP 7?
My post on the FreeRDP forum: https://github.com/FreeRDP/FreeRDP/issues/1827
Thanks,
Michael
Michael Eng