HelpVzipflip error

ok.. so I use vzipflip to find some armor mesh for swaping.. then i recently found error message from it

CSharpCode.SharpZipLib.Zip.ZipException: Cannot find central directory
at ICSharpCode.SharpZipLib.Zip.ZipFile.ReadEntries()
at ICSharpCode.SharpZipLib.Zip.ZipFile..ctor(String name)
at VZipFlip.Program.ConvertZip(String filename)
at VZipFlip.Program.Main(String[] args)

it worked perfectly yesterday.. but i have no idea why this got error today..

download zipflip again and install and try again