Ebay, open software HELP

I live in Washington state. I sold some unopened microsoft software on ebay. A person in Washington DC purchased the software, opened it, and said it was defective. I offered to exchange the software for her but she refused and wanted to send it back for a full refund, including the costs to send it back to me. I explained to her after software is opened it looses is value and I would no longer be able to sell it so I would only be able to exchange it for her (I take it back to where I got it and then they open and give me a new copy which I send to her). She refused and made a claim in small claims court against me for $150. I can't afford to fly across the country to make the apearance in court plus it would cost me more than the software is worth. This is not fair to me. For all I know she installed the software on her computer and wants to return it for and get it for free. This small claims court allows her to do just that and there isn't really anything I can do about it. Even if I do just refund her, I have an box of software that retails for $239, but its opened so now it is worth zip. Is there anything that I can do? If I were able to make an appearance in court would my case hold up (I have records of all the corespondences between us)? And if I did win, would I be able to make a counter claim recouping all the costs to me? (Flying out to DC, hotel room etc...)? Thanks for any advice on this matter.

Don't worry, you don't have to go to the other Washington. If you are served with a summons, your answer will be that the court in DC does not have jurisdiction and request that the lawsuit be dismissed. I use to be an avid eBay seller and was sued twice out of state, once in Ohio and in California. Both cases were dismissed based on the above. If the person in successful with a lawsuit, they will have to come to this Washington, have the lawsuit domesticated, then they can attempt any collection efforts. And domesticating judgments in this state can be a hassle, a lawyer is almost mandatory and the costs of domestication are not recoverable.

Thank you!

Thank you for your reply! I did some research and this seems like it will work since I do not meet the requirments for minimum contacts in that state. I want her to recieve a working piece of software, so if the case is dismissed I will still offer the exchange. I don't want to do bad business, but what she is asking is unfair to me. If I refund her, I am out a piece of software that retails for $236 and all the costs of selling and shipping it.

If she has the original software in the original packaging with the authenticy number,why can't she get a replacement directly from Microsoft herself for the defective software ?

they charge something like $25 plus S&H for the replacement cd while I could get it replaced for free from where I recieved the software.