Configure PowerConnect 3424 using Serial-to-Ethernet adapter

I've been desperately trying to configure my 3424 using a Serial-to-Ethernet adapter but have thus far had no luck. I've gone through the user manual, searched the forums and the internet but haven't been able to get anywhere. I purchased it pre-owned so it's already configured but I don't have the administration password to access the web interface and I can't establish an SSH connection so I'm assuming it's not set up. This leaves me with resetting the password but I can't do it without having access to it via a terminal connection.

I'm on Windows 7 using PuTTY for my terminal software but I've tried on Windows XP using HyperTerminal as well. I can provide any additional information needed as well but I'm not sure what else would help.