Win7 is a problem in many ways.
There is not enough detail in your message to provide a "smoking gun" that might point to the real issue.
You might try these things:
1. Win7 - Check and disable "home networking", if you run a mixed network using traditional methods it only slows your throughput to about 50%
2. Win 7 - Check your network properties on your interface. You want to allow 40 bit encryption (default for XP and below, 7 defaults to 128 which can make it incompatible.)
3. Linux side - check the configuration of your FTP server to see what IP it is listening on. Should be all.
Check this using "netstat -a|grep -i ftp". If the ftp listener is on 127.0.0.1 ONLY, then it is set to ONLY listen to localhost connections, not external.
4. Linux side - check your settings for firewall and selinux. If all else fails, disable firewall for a bit and test that way. If it works, you may need to change your firewall settings to allow teh ports for FTP inbound.
After trying/checking those, retry and let us know if it works or not. If it still fails, also report your findings and what symptoms you see.