Compress Directory and CompressFiles Error

[tablesmit]

When use the "CompressDirectory" or "CompressFiles" command
i get the Prefix number. Appears every file, folder,

https://drive.google.com/file/d/0Byc1YSB3Sd7xM0YzWjNCMER1NUk/view

[deltaone]

ArchiveUpdateCallback.cs

val = index + fileInfo.FullName.Substring(_rootLength);
->
val = fileInfo.FullName.Substring(_rootLength);