When backing up to a NAS CIFS Share the following error may be observed:
"Error 3208 - Can't read cifs:"
The error also ends with the word ".prepared"
vRanger is trying to verify .var file using cygwin on the CIFS share and unix extensions are being used, which breaks communication.
Disable "Unix Extensions" on the NAS device
You will need to contact your NAS vendor to do this.