Model : Archer C9

Hardware Version : ArcherC9 v1

Firmware Version : 3.17.0 Build 20150514 Rel.70681

ISP : NA

I recently switched to Archer C9 in my division at work. Prior to this I was using Ubquiti Nano station, and prior to that D-LINK wifi router. My setup is like this -

192.168.10.5 - windows pc dedicated for file sharing
192.168.10.6 - WAN IP for Archer C9
192.168.10.xx - Static IPs for all desktop machines

Archer C9 configured to DHCP : 192.168.0.100 onwards

What I couldn't do is access shared folder \\192.168.10.5 from any of the wifi connection. I checked c:\>telnet 192.168.10.5 445 (from laptop connected to wifi router) and it doesn't connect but I am able to telnet to any other port that is listening in 192.168.10.5. For example, I can browser intranet hosted in port 80 of x.x.x.5; remote desktop on port 3389 from one of the laptop to x.x.x.5.

Made sure firewall is not running in x.x.x.5, replaced Archer C9 with my previous wifi router and it works fine.

Can anyone tell me why can't I connect to port 445 of external network?

Archer C9 settings I have used
1. 2.4 and 5GHz both has same SSID name
2. 2.4 GHz has guest SSID
3. NAT boost disabled
4. Bandwidth cap for guest SSID and no network visibility
5. Printer share not used
6. File share not used (tired once and it works from internal n/w, doesn't work from 192.168.10.x n/w)
7. Bandwidth control disabled
8. Been using android TP-LINK app to check who are online