Sorry maybe i posted in the wrong location. I am just trying to load a file stream into the Infragistics workbook via the Workbook.Load(Filestream stream) function. And i am doing this in a dot net core 3.1 application using the latest package version 20.1.123 of the Infragistics.Web.Documents.Excel nuget package. But i am unable to load .xlsx and .xlsm files into the workbook and i end up getting an exception --> Invalid or unrecognized file format. (Parameter 'stream').

var client = new SftpClient("ConnString");
client.Connect();
using (client)
{
if (client.Exists("filename.xlsm"))
{
var fileContents = client.OpenRead("filename.xlsm");
var workbook = Workbook.Load(fileContents);
}
}

The only difference that I have in my use case is that my stream is not created using a local file in my code repo rather its fetched from a sftp server. If you can set that up locally, you will be able to reproduce my error.

Hello,

After further investigation, assuming the SSH.NET third-party library is used, the issue is in the OpenRead method. The workaround is to use a temporary file and the DownloadFile method of the library:

using (var client = new SftpClient(con))
{
	client.Connect();

	using (FileStream fileStream = System.IO.File.Create(tempFilePath))
	{
		client.DownloadFile(remoteDirectory, fileStream);
		workbook = Workbook.Load(fileStream);
	}
	System.IO.File.Delete(tempFilePath);
	client.Disconnect();
}