OK, my StreamReader was not being set to the encoding of the Tranform OutputSetting Encoding.  I was using this:

             MemoryStream ms = new MemoryStream();
             m_Transform.Transform(XmlData, TransformArgumentList, ms);
             ms.Position = 0;
             StreamReader sr = new StreamReader(ms);

So, something changed in this update because the server without the update was using UTF-8 encoding on the streamreader and it caused character 160 to 
essentially be stripped in the output.  On the server with the update it converted character 160 to 0xFFFD.  So, I corrected my StreamReader but 
something definitely changed in the update.  The transform was transforming to ISO-8859-1 then the streamreader was converting it to UTF-8, previously 
that was stripping character 160 from the output and now it converts it to character 0xFFFD.




Martin Honnen wrote:
> APA wrote:
>> I didn't say I was using the XslTransform class, I was generically 
>> referring to the XslTransform engine in .NET (and this is a .NET 2.0 
>> application).  The issue is clearly a problem with the update as my 
>> server that does not have the update doesn't produce the bad output 
>> but the one with it does.
>>
>> Here's a real simple example that produces the bad output.
>>
>>
>>         <xsl:stylesheet version="1.0" 
>> xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
>>             <xsl:output method="html" omit-xml-declaration="no"  
>> encoding="ISO-8859-1" />
>>
>>             <xsl:template match="/">
>>                 <b>&#0160;</b>
>>             </xsl:template>
>>
>>         </xsl:stylesheet>
>>
>>
>> This generates character xFFFD in the output where it produced a 
>> proper space character previously.
> 
> I have a Windows XP system here that on Wednesday got the security 
> update for KB928365. Using your stylesheet I made the following complete 
> test case
> 
> using System;
> using System.Collections.Generic;
> using System.Text;
> using System.IO;
> using System.Xml;
> using System.Xml.Xsl;
> 
> namespace ConsoleApplication106
> {
>     class Program
>     {
>         static void Main(string[] args)
>         {
>             XslCompiledTransform xsltProcessor = new 
> XslCompiledTransform();
>             xsltProcessor.Load(XmlReader.Create(new 
> StringReader(@"<xsl:stylesheet 
> xmlns:xsl=""http://www.w3.org/1999/XSL/Transform"" version=""1.0"">
> <xsl:output method=""html"" indent=""no"" encoding=""ISO-8859-1""/>
> <xsl:template match=""/""><b>&#160;</b></xsl:template>
> </xsl:stylesheet>")));
>             MemoryStream memStream = new MemoryStream();
>             xsltProcessor.Transform(XmlReader.Create(new 
> StringReader(@"<dummy/>")), null, memStream);
>             memStream.Position = 0;
>             StreamReader streamReader = new StreamReader(memStream, 
> xsltProcessor.OutputSettings.Encoding);
>             string contents = streamReader.ReadToEnd();
>             streamReader.Close();
>             foreach (char c in contents)
>             {
>                 Console.WriteLine("Character '{0}' with codepoint {1}.", 
> c, (int)c);
>             }
>         }
>     }
> }
> 
> The output on the console is
> 
> Character '<' with codepoint 60.
> Character 'b' with codepoint 98.
> Character '>' with codepoint 62.
> Character ' ' with codepoint 160.
> Character '<' with codepoint 60.
> Character '/' with codepoint 47.
> Character 'b' with codepoint 98.
> Character '>' with codepoint 62.
> 
> so the non-breaking space (character 160) is correctly included in the 
> output.
> 
> I can't reproduce the problem you describe.
> 
>