So if I am understanding this correctly, you want to do the following:
Windows Files Share ----> NiFi -----> Hadoop
Off the top of my head I can think of a couple ways to do it.
1) Setup the Windows directory to share via FTP. This can be done using IIS on the Windows machine, or a 3rd party FTP server
2) Install MiNiFi or NiFi on the Windows machine to transmit data using site-to-site protocol to the NiFi Cluster
Is there a particular reason you don't want to mount the share to the NiFi host?