How do I tell an unreasonable person that I can't help them with something on Facebook?

[vic_viper_001]

My mom just started using Facebook a few weeks ago. Ever since then, she's been using it ALL DAY EVERY DAY, and constantly asking me to do weird crap I don't know how to do. Things that there probably IS no way to do. I BARELY use Facebook and don't have a Twitter account, so I can only help with really basic things.

I've tried to explain that just because I'm on the internet a lot, it doesn't mean I know everything about Facebook, but my mom won't listen to this argument. She thinks that no matter how weird it is, there HAS to be a way to do it... even if there isn't. No amount of claiming not to know something or being unable to figure it out through Google searches will convince her that there are some things that just can't be done on Facebook.

Since I can't figure out how to help, I'm being made into an impatient villain who's unwilling to teach. How can I convince an unreasonable person that there are some things I just can help with... without being made into the bad guy?