Problems running WinUAE on Win2k

I am having a problem communicating with WinUAE on my Win2k desktop. I can download without any problems, but I cannot upload. Specifically:

E-mail: If I try to send a message, YAM will connect to the SMTP server, handshake, partially sends up the message, and freezes. I am able to send off small (100-200 bytes) messages without a problem.

Newsgroups: If I try to send a new post, Newcoaster will connect to the NNTP server and then freeze. I am able to send out small (100-200 bytes) messages without a problem.

FTP: I can connect to FTP sites, but am unable to upload files. Only the first 2-4k is sent before the FTP client freezes.

HTTP: No problems, but then I haven't tried to send up large files via HTTP

Ping: No problems

TraceRT: Does not work at all. I cannot even do a traceRoute to another computer within my LAN.

I can download e-mail, news, files, etc. without any problems at all.

The hardfiles and directories I use in this configuration are located on a network drive on my LAN. I use the exact same hardfiles/directories on my WinUAE installation on my WinXP laptop without any problems whatsoever. Configuration files between the two computers are identical. Same WinUAE version used on both computers. Within Win2k, I have no problems sending e-mail, news, or anything else.

My desktop and laptop are connected to my LAN and to the internet via a LinkSys DSL Router/Switch.

Now, here's the weird part: Everything worked on my Win2k desktop just a week or so ago. I had made some changes to Win2k's TCP/IP settings since, but have changed them all back. still, I am having no success making anything work. I have also tried re-installing WinUAE (08.22.R2), and have tried other WinUAE versions with no success.

Can anyone please help me shed some light on this bizarre problem? I have been pulling out my hair trying to figure this one out, and I'm nearly out of hair to pull!