Shot in the dark.. Network Transfer Slow

I was trying to transfer some files over my local network tonight. I am connected to a D Link Router. Both of the pc's were plugged into a cat 5 cable. My transfer speeds were 56k modem speed. I tried to search for hours on the web trying to find a cure. Anyone here ever run into that problem? I disabled firewall, defender, made sure both network cards were set to 100mb full duplex, and many other things. I finally gave up and burned what I needed on cd's. One pc is running Vista the other XP. I never had this problem before.

First thing I'd do is uninstall or disable the QOS Packet Scheduler - it's default ON for both OS's. It's overhead is immense, and it has absolutely NO use in a home network.

Your Anti-virus still active? Scan for spyware? Sounds less like you had a network problem and more like a disk IO or processing problem.

If you have anti-virus running on both machines, and the files are compressed but readable (like zip) and have alot of files in the zip or are just big files, this can cause MAJOR slowdowns in copying between systems.

No virus program. How do I turn that thing off in Vista and XP? It was many files but still that shouldnt give me 56k modem speeds.

Remember that tweak we had on here about TcpAckFrequency and speeding up the latency in WoW? If you've applied those changes to one of the PCs and not the other, you'll see strange behavior like this.

If you're in XP, it's network neighborhood properties, if XP it's Network and Sharing center - select properties for your wired network connection, uncheck or remove the QOS Scheduler.

Another thing to think about is cable routing. Make sure there isn't any large EMI (power cables, power strips etc) interfering. Had a cable fall from its perch and landed on a large power strip. Completely killed my transfer rate.