Hello Kaylan,

I am starting from a blank page, and I'm adding the controls and
dataconnections to it. I narrowed the problem down a little.
I does not seam to happen if the field has a Pascal cased name. For instance
if I have a field called MyProp and promote this property, then Infopath will
(automatically) promote it as My Prop. If I then add this property to my
Retreive connection it will be called My_Prop. I this case the problem does
not occur, so it looks like a good workaround.
Still, if the field names in the Submit and Retreive connection are equal
then I get an error when I submit the form. Here's the full trace of the
message:

Unexpected end of file while parsing Name has occurred. Line 1, position 207.

System.Xml.XmlException: Unexpected end of file while parsing Name has
occurred. Line 1, position 207.
at System.Xml.XmlTextReaderImpl.Throw(Exception e)
at System.Xml.XmlTextReaderImpl.Throw(String res, String arg)
at System.Xml.XmlTextReaderImpl.Throw(Int32 pos, String res, String arg)
at System.Xml.XmlTextReaderImpl.ParseQName(Boolean isQName, Int32
startOffset, Int32& colonPos)
at System.Xml.XmlTextReaderImpl.ThrowTagMismatch(NodeData startTag)
at System.Xml.XmlTextReaderImpl.ParseEndElement()
at System.Xml.XmlTextReaderImpl.ParseElementContent()
at System.Xml.XmlTextReaderImpl.Read()
at System.Xml.XmlLoader.LoadNode(Boolean skipOverWhitespace)
at System.Xml.XmlLoader.LoadDocSequence(XmlDocument parentDoc)
at System.Xml.XmlLoader.Load(XmlDocument doc, XmlReader reader, Boolean
preserveWhitespace)
at System.Xml.XmlDocument.Load(XmlReader reader)
at Microsoft.Office.InfoPath.Server.Xml.InfoPathXmlDocument.Load(XmlReader
reader)
at
Microsoft.Office.InfoPath.Server.DocumentLifetime.DataObject.<>c__DisplayClass3.<.ctor>b__0()
at
Microsoft.Office.Server.Diagnostics.FirstChanceHandler.ExceptionFilter(Boolean
fRethrowException, TryBlock tryBlock, FilterBlock filter, CatchBlock
catchBlock, FinallyBlock finallyBlock)
at Microsoft.Office.Server.Diagnostics.ULS.SendWatsonOnExceptionTag(ULSTagID
tagID, ULSCat categoryID, String output, Boolean fRethrowException, TryBlock
tryBlock, CatchBlock catchBlock, FinallyBlock finallyBlock)
at
Microsoft.Office.InfoPath.Server.DocumentLifetime.DataObject..ctor(EnhancedBinaryReader reader, Solution solution)
at
Microsoft.Office.InfoPath.Server.DocumentLifetime.DataObjects.<>c__DisplayClass2.<.ctor>b__0(EnhancedBinaryReader innerReader, DataObject& newObject)
at
Microsoft.Office.InfoPath.Server.Serialization.EnhancedBinaryReader.ReadObjectMap[KeyT,ValueT](Dictionary`2
map, ItemReaderDelegate`1 readKey, ItemReaderDelegate`1 readValue)
at
Microsoft.Office.InfoPath.Server.Serialization.EnhancedBinaryReader.ReadObjectMap[ValueT](Dictionary`2 map, ItemReaderDelegate`1 readValue)
at
Microsoft.Office.InfoPath.Server.DocumentLifetime.DataObjects..ctor(EnhancedBinaryReader reader, Solution solution)
at
Microsoft.Office.InfoPath.Server.DocumentLifetime.DocumentSessionState.DesterilizeVersion1(EnhancedBinaryReader reader, Solution solution)
at
Microsoft.Office.InfoPath.Server.DocumentLifetime.DocumentSessionState..ctor(EnhancedBinaryReader reader, Solution solution)
at
Microsoft.Office.InfoPath.Server.DocumentLifetime.DocumentSessionState.CreateFromByteArray(Byte[]
serializedSessionState, Byte[] serializedVersionState, Solution solution)
at
Microsoft.Office.InfoPath.Server.DocumentLifetime.DocumentSessionStateManager.GetSessionState(HttpContext
context, String editingSessionID, Solution solution)
at
Microsoft.Office.InfoPath.Server.DocumentLifetime.Document.LoadFromSession(HttpContext
context, SPSite contextSite, EventLogStart eventLogStart, Solution solution)
at
Microsoft.Office.InfoPath.Server.Controls.PostbackPage.<>c__DisplayClass1.<ProcessRequest>b__0()