The depends on what platform you're running Kodi on really. Usually it's either done via the Kodi machine offering a share, or using an S/FTP tool to move the file over. Then you browse to it in Kodi.
Addons I wrote &/or maintain:
OzWeather (Australian BOM weather) | Check Previous Episode | Playback Resumer | Unpause Jumpback | XSqueezeDisplay | (Legacy - XSqueeze & XZen)
Sorry, no help w/out a *full debug log*.