You could try posting the output of a traceroute to the SynIRC server that you connect to to see if it reveals where the blockage may be:
Can you browse to any site ? lf not, then that is a lot larger of a problem than what you first posted. Is the "Online" indicator light on the modem lit steadily ?
Does it indicate that you are in a general outage here ?;
I'm not having any other problems. I can go online and I can even access synIRC on my android device over WiFi. There's no outages reported near me. Yet for some reason I can't connect on my main computer with any client, and now apparently I cannot ping or trace route.
I've restarted my router multiple times today. After each restart, my IRC client was able to successfully connect to synIRC, but after a few minutes it would disconnect and not reconnect.
I reset Norton Security Suite's firewall and now I can ping again as well as adjust program control.
But this hasn't resolved my original issue with being unable to connect via mIRC
EDIT: I have noticed, I am unable to ping any of synIRC's servers via their IPv4 address. However, I am able to ping them by their network names (such as "avarice.ny.us.synirc.net") and the results are returned in IPv6
When I turn on a VPN, I am able to connect via mIRC, AND I am able to ping the IPv4 addresses. As well, pinging them by their network names returns their IPv4 addresses, not their IPv6 Addresses
EDIT EDIT: I am able to successfully connect via mIRC if I use the command specifically to connect to the server via IPv6, ie "/server -6 irc.synirc.net"
@ScipioAfricanus I have been having the exact same problem as you, and forcing it to connect via IPv6 like you suggested is the only thing that's been able to fix it. At least it's some solution. Please, keep me in the loop if you figure out anything else.
it looks to me to be solely related to Windows 10's new version 1903 probably. I had accidentally messed up my Norton firewall and it was blocking pings and traceroutes with IPv4, but I could still ping and trace with IPv6. I reset Norton firewall and everything's working again.
I still cannot connect normally except for using the command "/server -6 irc.synirc.net"
It only affects synIRC which is why I am confused.
Actually, it seems to be attached to some sort of new xfinity security suite they have on xFi or whatever it's called. It apparently detects some port usage as a threat. My roommate was messing with it earlier, and suddenly all my IRC problems dried up. I'll ask what specifically was done to fix it.