Hi,

I am using a BinaryReader to read an Excel 2007 file from an Exchange mailbox using a OWA, the file is then written to disk using a BinaryWriter. My problem is that the two files don't match when the writer finishes. Worse still Excel 2007 won't open the writen file.

Previously Excel 2003 has had no problem with the solution below. And Excel 2007 doesn't have an issue if the file is an Excel 2003 format file, only if the file format is Excel 2007 (*.xlsx).

BinaryReader:

using(System.IO.Stream stream = resource.GetInputStream(attachedFiles[k].Address))
{
    using(System.IO.BinaryReader br = new System.IO.BinaryReader(stream))
    {
        attachment.Data = new byte[attachedFiles[k].Size];
        int bufPosn=0, len=0;
        while ((len = br.Read( attachment.Data, bufPosn, attachment.Data.Length-bufPosn )) > 0)
        {
            bufPosn += len;
        }
        br.Close();
    }
}

BinaryWriter:

FileStream fs = new FileStream(fileName, FileMode.Create);
BinaryWriter binWriter = new BinaryWriter(fs);
binWriter.Write( content, 0, content.Length );
binWriter.Close();
fs.Close();

Suggestions gratfully received.