Router settings to allow MacPro to access corporate VPN through router

Judging by the port numbers you listed, you are trying to setup a VPN tunnel to a corporate network. If this is a client based VPN, you actually don't need to open these ports at all, given that the router will allow all traffic outbound, by default. However, if you are trying to build a site-to-site VPN, your Linksys router isn't capable of this.

Now, I suppose you may have a device inside your network, behind your router, that is running some VPN software of some sort. In which case you want to turn on port forwarding. This can be a complicated task. Please comment, if that is the case and I will go into more detail.

Use the web interface to administrate settings.


Netgear:
192.168.1.1
user: admin
password: password or 1234


Go to Advance > Default DMZ Server and enter the computers IP that needs VPN access. This will bypass routers NAT / Firewall, and allow all network ports access.

It probably has something to do with the fact that this particular model is not meant for personal use, but in big corporations. It does not support UPnP which allows possibly harmful programs that are accessing your router to auto configure the security settings on your router. If you got any more problems with your router, maybe you should check out this cool users manual. It really helped me a lot, maybe it will help you, too :)

You may have to link up with your IT department at work and have them list your linksys router for access to the corporate network.

This should help.

The netgear prosafe VPN router is a high-end component ment for business and corporate use and does not support UPnP

UPnP (Universal Plug and Play) allows programs accessing your router (limewire, utorrent, etc...) to auto configure the security settings on your router which would be harmful to a business/corp. network.

check that the VPN setting at the office allows NAT TRAVERSAL

Did you already forward port 1723? I guess you have done that. To isolate it, try to bypass the router and setup or establish the VPN session there. If it doesn't work, maybe your ISP doesn't allow port 1723 or it's just the modem.

That 3Com really doesn't have a wahy of setting up a VPN.
As per the 3Com site it:
Support of VPN termination/initiation and passthrough allows secure connection to central office and/or secure access from remote workers.
So it will allow 3rd party VPN setups to pass through, but it doesn't have the ability to create one.
You might want to look into something like a Netgear Firewall
http://www.netgear.com/Products/VPNandSSL/WiredVPNFirewallRouters/FVS114.aspx

Microsoft uses IP Protocol 47 [GRE] for this secure tunnel. Provided that the PPTP Pass Through is set to Enable on the Router's Filters page and port 1723 is forwarded to the VPN Server, the Router will allow authentication and remote access into your network. The router will also allow you access remote PPtP networks from behind the router providing the PPtP Passthrough is enabled on the router.