Thanks for your quick response Robbert,

AS for the WSE350 exception, it is thrown from the WSE 2.0 DIMO
attachment's deserialize code as the callstack you provided as indicated.
It is the "Microsoft.Web.Services2.Dime" class's "close" method that throw
this exception. In this method,  it has the following code logic:

** check if the the upstream code has marked the message as arriving end

** if marked as end, it will compare the current readed bytes length with
the message's content lengh field(get from the DIME message).

** if the value mismatch, it will report the exception as you encountered.

Here is the disassembled code through reflector:

============================
internal void Close(bool endOfMessage)
{
     if (!this.m_closed)
     {
           this.m_closed = true;
           if (this._mode == FileAccess.Read)
           {
                 if (this.m_bytesReadWritten == this.m_contentLength)
                 {
                       if (!endOfMessage)
                       {
                             return;
                       }
                       return;
                 }
                 throw new DimeFormatException(SR.GetString("WSE350", new
object[] { this.m_id, this.m_contentLength }));
           }
           if (this._mode == FileAccess.Write)
           {
                 if (this.m_chunked)
                 {
                       this.WriteChunkedPayload(true, endOfMessage);
                 }
                 else if (endOfMessage && !this.m_endOfMessage)
                 {
                       this.WriteMessageEndRecord();
                 }
                 else if (this.m_contentLength == 0)
                 {
                       this.WriteHeader(true, (long) 0);
                 }
           }
     }
     else if ((endOfMessage && !this.m_endOfMessage) && (this._mode ==
FileAccess.Write))
     {
           this.WriteMessageEndRecord();
     }
}
=================================================

Therefore, I think the code logic here is very straightforward, also I
don't think it is your application's code logic that will cause this error.
Very likely that the DIME message's content has been corrupted over the
wire.

Sincerely,

Steven Cheng

Microsoft MSDN Online Support Lead

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