As long you neither you nor we know what they did in the shop, it's not really possible to tell you how to undo it.

And if you don't even tell the errors, but limit yourself to "no longer works" and "can't send" you don't give enough information to the forum to get any effective help.

Two things you can do:
- go back to the shop and let them fix it
- uninstall and reinstall aol software

Hope this helps.