How to create XSD from XML

I'm looking at that at the moment, but it's not an out of the box solution. It seems to need quite some work.

My experiences:
When using XSD.exe it's important to check whether you're using the 32 or 64 bit version, the 32 bit version crashed after five seconds while the 64 bit version actually ran for almost four hours before running out of resources. My conclusion is that if the file fit's in memory, the 64-bit version of XSD.exe would have done the job.

Instead I ended up using the XmlReader finding all element names using this code that I found on the net:
Dictionary<string, list<int="">> nodeTable = new Dictionary<string, list<int="">>();
using (XmlReader reader = XmlReader.Create(documentPath))
{
while (reader.Read())
{
if (reader.NodeType == XmlNodeType.Element)
{
if (!nodeTable.ContainsKey(reader.LocalName))
{
nodeTable.Add(reader.LocalName, new List<int>(new int[] { reader.Depth }));
}
else if (!nodeTable[reader.LocalName].Contains(reader.Depth))
{
nodeTable[reader.LocalName].Add(reader.Depth);
}
}
}
}
Console.WriteLine("The node table has {0} items.", nodeTable.Count);
foreach (KeyValuePair<string, list<int="">> kv in nodeTable)
{
Console.Write("{0} [{1}]", kv.Key, kv.Value.Count);
for (int i = 0; i < kv.Value.Count; i++)
{
if (i < kv.Value.Count - 1)
{
Console.Write("{0}, ", kv.Value[i]);
}
else
{
Console.WriteLine(kv.Value[i]);
}
}
}

Console.ReadKey();
And then searching the document for all Elements, cutting and pasting all Items to a new document containing all existing elements. And then I ran Xsd.exe on that file.