Okay Gus,
I need you to make sure if your using XP that the firewall has not enabled itself without you knowing, incidently I think its wise especially with XP to have some sort of firewall protection, so you may want to use the XP and map the ports that WinMX is set to use through it.
Instructions on that here:
https://www.winmxworld.com/tutorials/firewall.htmlAlso its worthy to note here that Shaw is using a few forms of filtering and throttling of your P2P use, well for many of their cutomers this is true, and you may be one of them. If they are doing this in your area changing the ports that WinMX normally uses may also help you with this.
Change the ports you use in WinMX, some that have been used that folks have had success with are the following:
Listen on 1720 for TCP
Send and receive on port 39 for UDP.
Listen on 1035 for TCP
Send and receive on 443 UDP.
Listen on 58202 for TCP
Send and receive on 61202 UDP
Listen on 1547 for TCP
Send and receive on 5631 UDP
These are some ports that have been proven to work, not in all cases tho.. but its worth a try.
To change ports go to WinMX Settings> Internet Connection > Incoming TCP ...
Then IN/OUT UDP...
Make the needed changes there, be sure to also change these in any firewalls, router/modems that you have forwarded for specific ports.
If you only changed in WinMX a restart of WinMX is all that is necessary for them to take effect.
If you made changes to any firewalls or router configurations its best to reboot the computer.
Normally its the Upload traffic that is affected by the ISP, or your downloads and uploads will at least connect but then slow to a crawl, so what I mean is you will usually have download ability even if your ISP is filtering p2p.
Another thing you might try is to set your Ports in WinMX to
'Unable' for both Incoming TCP and IN/OUT UDP.. then restart as a secondary connection. IF this works then its more then likely a settings issue and not your ISP.