Hi Sunagwa. Let the software search for the com itself. Go to 'options' then "set comport" then hit auto detect. Then you can check the recommended settings for the com. Sounds like the DB9 cable may have got smoked when you plugged it in. At Meade's website they have the instructions on how to hook them up and use the software. Leave the scope shut off when hooking up the cables.
Good Luck.