Strange Email Routing Issue.. COMPLEX!

[Crazy Buddhist]

Well, I know that there are no devices between the wi-lan adapter, and the switch that feeds the linksys and the cisco routers. I traced the wire right from the roof into the switch, and then plugged the routers into the switch myself.

Does he have to log in to the company network over the wireless to use the internet?

[Luke122]

The business network is all ethernet in the building, and wireless from there back to the ISP.

[billygoat333]

linksys sucks... i have always had problems with their routers. I just felt like interjecting that, have no idea what could be causing this, besides maybe a setting in outlook? i dunno. Tried updating outlook? what about connecting to a different mail server and downloading an email with attachments? does that work?

[Luke122]

Update: I tried replacing the Linksys Router (RV-042) with a cheapo Dlink Di-624 (home wifi router), and the problem persists.

I get the feeling that the ISP is having troubles routing the mail correctly. Could be that they cannot route the same IP through 2 different paths, I dunno.

I've notified the ISP of the issue again, and let them know all the troubleshooting I've done so far to address it, we'll see what they come back with.

-Luke

[Crazy Buddhist]

Update: I tried replacing the Linksys Router (RV-042) with a cheapo Dlink Di-624 (home wifi router), and the problem persists.

I get the feeling that the ISP is having troubles routing the mail correctly. Could be that they cannot route the same IP through 2 different paths, I dunno.

I do not see how they can route one IP address to two devices.

[Luke122]

They cant, as no two devices have the same IP.

What I meant was that his laptop has the same internal IP, regardless of whether he connects through the company VPN, or connects through the linksys (or replacement router).

The cisco and the linksys each have a unique external IP, but his laptop IP is the same regardless of which one he connects to.

Hope that clears it up.

[Crazy Buddhist]

They cant, as no two devices have the same IP.

What I meant was that his laptop has the same internal IP, regardless of whether he connects through the company VPN, or connects through the linksys (or replacement router).

The cisco and the linksys each have a unique external IP, but his laptop IP is the same regardless of which one he connects to.

Hope that clears it up.

Thanks Luke ... This is related to the question I asked earlier ... "Does he have to log in to the company network over the wireless to use the internet?"

If his laptop has the same IP its either a fixed IP in the TCP/IP properties or the DHCP server has assigned it permanently to his laptop ...

I'm going with the DHCP server doing this which implies the same DHCP server is issuing the addy whichever router he connects through ...

I get the feeling that the ISP is having troubles routing the mail correctly. Could be that they cannot route the same IP through 2 different paths, I dunno.

The ISP has nothing to do with the routing once it hits either router. The router does all the work from that point on. His internal IP being the same is only known to the internal network.

I still believe the only difference is that at either a hardware or software level on the corporate network the Linksys, being directly connected to the net, is being subjected to more stringent firewall rules re attachment downloads than when connecting through the VPN.

This would make sense from the first network installation/design point of view: as through the VPN colleagues should need to be able to share documents with each other, but out to the word wide web greater restrictions make for greater safety.

That's my take on what's going on: Somewhere along the line there is a corporate level firewall being the bad boy.

[Luke122]

SOLVED!

Removed the Linksys RV042 router, and replaced with D-Link DFL-700, and its all good now.