Computer receiving packets but not sending

I haven't been able to find any information concerning this and I was hoping someone could help me. I've found posts and information on problems with not receiving packets but not with not sending packets. I'm connecting through a RCA broadband modem with Roadrunner cable service and a 3COM Etherlink NIC. When I start my computer, it never sends packets. I have to pull out the ethernet cable and replug it to reconnect. After a few tries, it'll connect. Occasionally my computer stops sending packets and I disconnect and I'll have to reconnect by unplugging and replugging the cable. What's the problem?

that happened to me twice. my solution has always been to turn off both the modem and my router by disconnecting the power cable and then unpluging all connections. then i turn on my modem....after that is on and has a connection.........start the router....then finally restart of pc and plugging in the ethernet cable into the computer.

or just basically restarting everything

Yea, it works whenever I do that too but the problem is I have to do it every single time I log online and whenever I disconnect. It's not a huge problem but it gets very annoying