Constructed from the て-form of verbs, から ‘from’, で, ない, and と, てからでないと is a grammar pattern that expresses that ‘unless (A), (B) will not happen’, or ‘until (A), you cannot (B)’. Due to this, the (B) part of sentences that use this grammar pattern will always be negative.
This structure simply indicates that (B) must come after (A). This could be in relation either to (A) and (B) being finished, or simply to (B) becoming possible after (A).

• 全（すべ）ての書類（しょるい）が揃（そろ）ってからでないと、本（ほん）申（もう）し込（こ）みができません。
  You can’t submit the actual application unless you have all the documents.
• このアプリをインストールしてからでないと、携帯（けいたい）に入（い）れた音楽（おんがく）は聴（き）けません。
  You cannot listen to the music you put in your phone until you install this app.

Alternatively, the hypothetical ば form may be used instead of と. This will appear as てからでなければ.

• 資格（しかく）をとってからでなければ、面接（めんせつ）が受（う）けられません。
  Unless you get the qualification, you cannot be interviewed.
• その件（けん）については上司（じょうし）と相談（そうだん）してからでなければ、ご回答（かいとう）できません。
  I will not be able to respond to you until I have discussed this matter with my supervisor.

てからでないと can be thought of as an extension of the base てから grammar pattern that expresses that (B) only happens after (A).