web services - UpdateListItems throws "Cannot access a closed Stream." -

i have been trying find out issue faced documents while uploading in libraries using list.asmx service in web application.
steps follow:

1. uploads document using copy service.
2. update uploaded document properties.

i facing issue documents while updating properties. don't know whether document size or document type causing problem. if document size or type, might wrong have uploaded similar document same type , larger size no exception.
following code using update document's properties.

        xmldocument doc = new xmldocument();         xmlelement batch = doc.createelement("batch");         batch.setattribute("onerror", "continue");         batch.setattribute("listversion", "1");         batch.setattribute("viewname", viewname);         batch.innerxml = "<method id='1' cmd='update'>" +                          "<field name='id'>" + id + "</field>" +                          "<field name='" + columnname + "'>" + colvalue + "</field></method>";         xelement xelement = utility.toxelement(batch);          //listssoapclient object         var proxy = utility.getserverlistproxy();         proxy.updatelistitems(listname, xelement); 

exception is

fault exception details:

cannot access closed stream.

thanks in advance.

later figure out that, document trying upload has weird characters other special characters in file properties attributes.

so after removing characters, working fine.