ReadyNAS 214 - New PC but same hard drive contents, how do I index the old path?

Hi everyone, I have an 8TB internal hard drive in my computer that has all of my photos etc. Everything is neatly organized. I use the ReadyNAS "Backup PC Folder" setting to mirror the folders in my internal hard drive to the NAS. I use this as a backup solution.

However, I just bought a new motherboard and cpu, and I am trying to tell ReadyNAS to check the existing files on the NAS, as nothing as changed. Instead it is trying to re-copy everything over in a new folder. If I rename the folder while it is indexing, it gives an error. Is there a way around this? Other than copying everything over again...

Thanks