Dim compressor As New XceedStreamingCompressionLib.XceedStreamingCompressionClass() 

compressor.License( "your license key" ) 

compressor.CompressionFormat =
                     New XceedStreamingCompressionLib.XceedBZip2CompressionFormatClass()      

Dim sourceData As Object = "This is the data to compress compress compress"

Try
  compressor.WriteFile( sourceData, XceedStreamingCompressionLib.EXCFileProcessing.cfpCompress, 
                        true, "c:\test\file.cmp", false )
Catch except As System.Runtime.InteropServices.COMException
  MessageBox.Show( except.ToString() )
End Try

Dim compressor As new XceedStreamingCompressionLib.XceedStreamingCompressionClass() 

compressor.License( "your license key" ) 

compressor.CompressionFormat = New XceedStreamingCompressionLib.XceedBZip2CompressionFormatClass()

Dim bytesRead As object = Nothing

Try
  Dim decompressedData As Object = compressor.ReadFile( "c:\test\file.cmp", 0, 0,
                XceedStreamingCompressionLib.EXCFileProcessing.cfpDecompress, true, bytesRead ) 

  MessageBox.Show( System.Text.Encoding.Unicode.GetString( CType( decompressedData, byte() ) ) )

Catch except As System.Runtime.InteropServices.COMException
  MessageBox.Show( except.ToString() )
End Try