remote desktop thru VPN not working

[M_Rossi]

We currently have a Fortigate 60C. We are using this to VPN in to the office. We then remote desktop to the computer we to use after logging in thru the VPN. I have one user that is not able to remote to their computer from home. It had previously worked but stopped. For testing I was able to login to the VPN thru the outside wifi, and remote into his pc. I also tried to login from my home to the VPN and them remote to his pc, works fine. If he tries it from his house, logging in to the VPN and then “remote desktoping” into his pc he gets this error: “Remote Desktop can’t find the computer “XXXX” This might mean the “XXXX” does not belong to the specified network. Verify the computer name and domain that you are trying to connect to.” The name of the pc is correct and the domain is correct. Any other ideas of why it will not connect? Thanks for any help.

[billp]

This is a longshot, but is there any chance that the subnet in his house is the same as the subnet of the remote computer? In other words, if his subnet at home is 192.168.1.0/24 and the subnet of the remote computer is the same, then you could have a routing issue. This could especially be the case if he updated home routers recently.

[M_Rossi]

Thanks for commenting. The user may be using this subnet at home but we are not here at work. Internally we are using 10.0.0.X, so his pc here will have an ip in that range and we have our external ip address range from the isp. So I don' t think this is the issue, however, I believe he mentioned to me about an update of his router to a wireless router. I also think he has Comcast and we have that in the office too. Any other suggestions are welcome.

[ede_pfau]

I would rather think that using the same IP address range on both sides of a VPN tunnel will make routing helpless. How come you think that it won' t matter? Besides, reading your first post, I would have checked the DNS the user is using. Can he connect using the server' s IP instead of it' s name? Can he ping the server, or any other (permanent on) host, like a printer?

[M_Rossi]

I agree using the SAME ip address scheme on both end would cause issues. We are not using the same ip address scheme. So I think it rules that out. I do not know if he can ping the pc’s ip in the office. I am not at his house to test and he is not the most computer literate. I was able to tie in at work using his laptop thru a local wifi and all worked well. I am also finding he recently replaced a router thru Comcast …Wondering if that could be an issue. I am still troubleshooting and narrowing this down. Thanks for the help.

[kolawale_FTNT]

It had previously worked but stopped.

Would you happen to know when it used to work and what changed just before it stopped working? It may give some ideas of where to look for issues. Fortinet customer support may be able to troubleshoot this with you.

[M_Rossi]

I did ask the user if he loaded anything or something changed. From what he says, the only thing that changed around that time is his wireless router from Comcast. However, he insists it worked a few times after the install of the new router. I am exploring this and asking him to call Comcast to see if they are blocking it somehow. I have been on other sites and they ask for the router type and very specific information. I would only be able to get if I go to his house (the user is not very computer literate). Has this been found to an issue in the past? Is so and I need to get more info I will get it. Thanks.

[kolawale_FTNT]

Have not seen any similar reports of RDP blocked after a successful VPN connection. Based on your original posting and response to comments, it works for everyone else. It also works for him when he is not using his Comcast router (such as when you tried from the office). You may want to further investigate his Comcast router.

[M_Rossi]

Well it is fixed. The user called Comcast and when he mentioned the VPN stopped working the response was to upgrade to the business class connection for his house! What? :0 I figure it is as I read in other forums, something on the router blocking the VPN connection. They turned off the wireless on his new router and setup a wireless router he had and all is well. Unbelievable. Thanks for all the help and suggestions.