When you Serialize a pivot grid control that was deserialized with a filter, you get a null pointer exception.
I'm attaching a sample project to test this.
Steps:
1) Drag and drop "Product" column to the "Filter Fields" area
2) Click Serialize
3) Click Deserialize
4) Click Serialize again -> Here you get a null pointer exception that comes from the SerializedXmlString method.
Attachment:
SampleSerialDesSer_744e1d31.zip