WORKAROUNDS: - set OutputType to SVG_VML - set ShowChecksum to false Sample problematic setups: <telerik:RadBarcode runat="server" ID="RadBarCode2" Text="238.339.6814" Type="Code93Extended" OutputType="EmbeddedPNG" ShowChecksum="true"></telerik:RadBarcode> <telerik:RadBarcode runat="server" ID="RadBarCode1" Text="238.339.6814" Type="Code93" OutputType="EmbeddedPNG" ShowChecksum="true"></telerik:RadBarcode>