@slamjam 

I myself have two ER707-M2 with site to site vpn, there have never been such problems, do you have any screenshots of the vpn configuration?

Do you have other VPN services on the router such as openvpn or SSL vpn? I have had similar problems as you describe on ER8411 but then SSL vpn has been configured, I had to delete all SSL vpn configuration before site to site worked properly. I haven't tested SSL on the ER707-M2, so I don't know if it's the same problem there

  @MR.S 

Thank you very much, here the configuration. On the other side i don't have any SSL vpn configured on the omada side. 

  @slamjam 

you should not use this encryption, it is outdated and insecure, try this one instead.

Do you have SSL on any of the routers?

Is there ER707-M2 on both sides of the tunnel?

  @slamjam 

You have Fortinet I see, sorry I didn't see that.
try with slightly stronger encryption, I have vpn against cisco, unifi, sonicwall and microtik, it works without problems, but I have not tested with the same encryption as you have

  @slamjam 

I am quite sure that the problem is not on the ER707-M2 if you have not configured other types of VPN on it, I asked you if you have configured SSL VPN on the ER707-M2, you have not answered this yet.

to test comunication.
can you telnet to the server that has the file share.

in windows you can type that command in the command prompt,

telnet 192.168.56.1 445

ip is an example, replace with ip to server where file share is
if you do not get a response, you must check that nothing is blocked in the Fortinet firewall

if you dont have windows telnet add windows function in add remove program.

  @slamjam 

I have done some more tests on my ER707-M2 routers, SSL works fine with this router combined with site to site, only way I can provoke what you have is by blocking TCP port 445. then file explorer hangs and finally it doesn't respond.

  @MR.S 

thank you veru much for the support that you're giving. 


i've tried and the port 445 is open. 

What is very strange is that on the fortinet side the configuration is exactly the same for all the vpns (other sites and ssl)

PS i've done another check, i've a nas with an smb share and it works! So it's some strange configuration regarding something regarding windows shares (but remember that this shares works with the ssl fortinet vpn)

  @slamjam 

have you remembered to open the widows firewall for the network that is on the ER707-M2, the windows firewall blocks deafult remote networks