Mike:
This isn't an easy one.
I can give you several things to check and try.
The only real clue you gave us was a change in connection venues. And the fact that you are using Microsoft Windows.
Are you using a Nat or firewall on this computer and is it on?
Do you run regular checks for spyware and viruses on your computer and is your antivirus and spyware software updated?
What Windows OS are you running and how long since you updated it and since the time you installed or reinstalled it?
Are any other programs having problems?
Some DSLs provide a Nat and or firewall either at their source and/or with the modem/router, but it usually has to be switched on. Broadband I haven't been on in a year plus and am not sure of the measures they take, currently. If you are running Windows XP, make sure that firewall is on.
The fact is that a computer running Windows needs to have the hard disk reformatted and the operating system reinstalled every year or two, according to the experts and my own experience. Drivers and other software can deteriorate over time and need to be reinstalled.
Broadband and DSL tend to be more open and faster than dialup and can be more vulnerable to hacking, viruses, etc. Your problem could be a piece of spyware interfering with Xtreme. Or even another legitimate piece of software not working or playing well with Xtreme. Did your Broadband provider require you to install any software on the computer to help connect?
If you've started experiencing other program problems it could be an indication of windows .dll issues. and a need to reinstall Windows, or wait for more problems and do an Internet search on those issues.
When you uninstall Xtreme, do you restart your computer before you reinstall the program. Will help clean out the registry (some) before you reinstall, especially if the problem is partly or totally with the registry. If you are enough of a techie to get in and check the registry and make sure the Xtreme entries are cleared out. Otherwise, "Don't try this at home".
More complex than you hoped? I've become a closet techie through need and dealt with problems like this on my own computers and family computers.
I may not be on the forum for a couple of days, but will check back
by Monday.
Good luck,
Scott