If you had been using a Proxy and removed it did you check IE, under Options / Connection / LAN Settings to see if the Proxy box is still checked?
Here is a good speed test site (don't get sucked in with all of the june "speed up my PC" ads, just do the BW test and see that you are really getting the bandwidth you expect, if not, make it ATT's problem again. http://www.speedtest.net/
My computer has been acting weird lately. I use the Zune marketplace and Playon for my PS3 and whenever I try to sign in or use the programs they say that they cannot connect to the server or the bandwidth is low even though I'm getting 3mps. Even when I try to download templates for Microsoft word within the program. I've tried all of the troubleshooting that various tech support people have walked me through like allowing the programs on my AVG, disabling my firewall, etc and even getting rid of it completely but no luck. I can use the internet just fine and have run all the virus, spyware, and malware programs I have and like normal everything comes out clean. My computer did do something weird the other day though, it wouldn't get on the internet but then I got rid of my proxy and it was fine again but my programs still don't work. I've also called my ISP and there's nothing wrong with the line but whenever I use AT&T's self support tool it says that there is a problem with my connection even though it doesn't show it on their end. It also says that my line state, DSL state, and Ethernet status is down whatever that means.
I am running windows Vista 64 on an HP Pavilion m9340f.
I am OK with computers but not great and would appreciate any help y'all can give,
P.S. is there a good trustworthy program I can download to search for and fix problems like these that might help? I have Glary Utilities but that didn't work...