Note that PuTTY is a great, free, opensource application. It's a bit basic and has no real scripting support. I've used it for connecting to Option 11c switches on and off for a couple years now. However, if you have an older system with Meridian Mail, you may have problems with PuTTY. I could never get the terminal emulation to work correctly when dealing with Meridian Mail. If you are only accessing the LDs, etc, it works well.
When I deal with Meridian Mail, I use a commercial application called SecureCRT. I'm sure there are other options out their as well, but it's the one that works for me.
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