Using FileStream and XmlSerializer: Gives me the error:The instruction at "0x635e0719" referenced memory at "0x00000000". The momory could not be "read

[antsays]

I am trying to serialize a collection to disk using the code provided.

This works just fine but when I try do copy and past the xml file to
another location or sometimes even just click on the file it gives me
the error: The instruction at "0x635e0719" referenced memory at
"0x00000000". The momory could not be "read.

Could anyone please help out with this
I also tried putting the code in a try catch finally and closed the
filestream.

Here is the code in the simplest form

XmlSerializer serializer = new
XmlSerializer(typeof(SSHistoryEntryList));

using(FileStream fileStream = new FileStream(file.FullName,
FileMode.Create, FileAccess.Write, FileShare.Read)) {
serializer.Serialize(fileStream, historyEntryList);
}