Visit her.

You: "Hi <insert her name here>. I'm here to take care of your computer problem."
Her: "Oh? What is the problem?"
You: "Well, your computer is a totally inappropriate means of asking you out for lunch, so I thought I'd come over and see to it personally. So, would you like to go out and grab a bit to eat sometime?"
Her: "That is so sweet. I want you now!"