There is an issue with SharePoint 2010’s CAML parser that causes SharePoint to ignore fields in a Content Type definition. When defining a Content Type feature element, avoid placing comments inside the <fieldrefs> element as that will cause SharePoint to create the Content Type disregarding all the fields, even though the XML is well formed.
<?xml version="1.0" encoding="utf-8" ?>
<Elements xmlns="http://schemas.microsoft.com/sharepoint/">
<ContentType
ID="0x0100C5647A362F236548B218C15302286758"
Name="MyCT"
Description="Simple Custom Content Type"
Inherits="TRUE"
Overwrite="TRUE"
Version="0">
<Folder TargetName=”_cts/MyCT” />
<FieldRefs>
<FieldRef ID="{fa564e0f-0c70-4ab9-b863-0177e6ddd247}" Name="Title" />
<!-- This is a comment –->
<FieldRef ID="{b402db15-ee44-4ec4-89e3-23e10a8fc64c}" Name="My_x0200_Field" />
<FieldRef ID="{538c71e4-8650-4ce7-b021-920effa66346}" Name="Status" />
</FieldRefs>
</ContentType>
</Elements>
The Content Type feature element above will cause the Content Type to be created with only the Title field, which is inherited from the parent Content Type. All the fields referenced in this Content Type definition will be ignored.
