[Eroh]

If you're reading this thread with the same issue, hope some of the above suggestions do it for you... will update if I find a solution.

I've run into a similar issue and found my own solution, and while I don't think this will help you (the OP), I wanted to post this for anyone else who found this thread while searching like I did for solutions. I have run XBMC/Kodi on Windows since the death of Boxee (the Windows app, not the hardware) and never had any issues connecting to a network share. Just got the new Fire TV and could connect to one folder on an external HD with Kodi (15.1 and 14.2) but not a folder on another external HD (both connected to the same Win 10 PC). And could connect to a share on another Win 7 PC. Kodi could see the folder, but when I tried to open it I would get 'Error - Invalid Argument'. My instances of Kodi running on Windows could still open/read all these folders. Based on Google searches (which is how I got to this thread), I did a registry edit, changed ownership and permissions on the problem folder, unplugged/restarted the HD and PC multiple times, and finally moved all the files and formatted the external HD. Nothing helped. Even installed different versions of Kodi on the Fire TV with no change.

Then I realized that the HD I could read was plugged directly into the PC's USB 3.0 port while the one I could not was plugged into a USB 3.0 hub (itself plugged into the PC's other USB 3.0 port). When I switched them, Kodi could read/open the media folder on the original problem HD and no longer read/open the folder on the previously working HD. While I am happy I can see my main media folder using Kodi on Fire TV again, I am questioning the quality of the USB hub (HooToo) which worked fine with Windows/Kodi but not the ARM version. What could be so different between the two, as I think (well, assume) they are both using the same SMB protocols in both cases? The hub doesn't have any obvious problems, seems to have good speeds, and has never had any similar issues with Windows shares.

Anyway, I hope this helps somebody (though in retrospect it now seems like it took me 2 days to find the simple solution that I have to assume some others might try first).

[nechemias]

I've experienced a similar problem:
- Amazon Fire TV / Kodi (latest version as of June 2016)
- SMB share from external drive (Win 10 Pro, all permutations of rights and ownership)
- Connected through 3.0 USB hub, but plugging directly into root, on-board USB hub had no effect
- Share worked fine for all network devices except Kodi on Amazon Fire TV
- Got "Invalid Argument" when trying to connect from Fire TV

THE FOLLOWING FIX WORKED FOR MY SETUP:
- Regedit
- Backup root registry key (right-click, Export)
- Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters
- Create a new DWORD called IRPStackSize (if it doesn't already exist). Set it to a decimal value of 50.
- Reboot PC/Server
- Reboot Fire TV
- After reboots (not before... I tested, just to see), I connected fine from Fire TV/Kodi, using local account username and password

When I tried the value posted elsewhere for IRPStackSize (21), it had no effect on the Fire TV "Invalid Argument" issue, but I did get an error in the Windows Event Log on the host machine that made me try the older maximum value of 50:
- Event 2011, srv: The server's configuration parameter "irpstacksize" is too small for the server to use a local device. Please increase the value of this parameter.

I hope this helps some of you...