After the verb 'to tell', you always refer to the person that received the information. If you don't want to refer to that person, you can use the verb 'to say' instead.
Did + past participle (told) isn't possible so it could be: The simple past: What did she tell you? The present perfect: What has she told you? (if the action has taken place just now!) The past perfect: What had she told you?