XceedZipLib.XceedZip zip = new XceedZipLib.XceedZipClass();

zip.License( @"your license key" );

// Specify which files will be added to the zip file
zip.FilesToProcess = @"c:\windows\fonts\*";

// Specify the name and location of the zip file.
// If it does not exist, the zip file willbe created.
// If it exists, it will be updated to contain the new files.
zip.ZipFilename = @"d:\fonts.zip";

// Zip the files
XceedZipLib.xcdError result = zip.Zip();
MessageBox.Show( zip.GetErrorDescription( XceedZipLib.xcdValueType.xvtError, ( int )result ) );