What is transaction not found on blockchain mean? Does that mean transaction still waiting in mempool, unconfirmed or never broadcasted on blockchain? I requested from my exchange (GEMINI) to withdraw bitcoin and send to my another exchange (BITTREX) on 11/11/17, four days ago. I have still not received my bitcoin at BITTREX receiving exchange; the transaction does not show in pending at receiving exchange.

Gemini exchange transaction history shows a withdrawal of bitcoin transaction with a link 'view transaction'. If I click on this link it takes me to https://insight.bitpay.com/ and shows "TRANSACTION NOT FOUND". I also searched in blockchain.info and some other explorers all show transaction not found.
So far not much luck from Gemini support. I am getting desperate with Gemini.

Here is the transaction ID;
e1e405bdd06b3ab23c3099f41f5da58ea0f5cf0bd2f891850c1d5c70fedfdb20

What is happening with this transaction?  What does "transaction not found" mean?


Is this waiting in miner's mempool to be picked up?  
Is this unconfirmed and already dropped from the blockchain network.  
Transaction have some error to start with and never broadcasted on blockchain network?  
None of the above and have some other issue?
Is this waiting in miner's mempool to be picked up? 
  


No. Broadcasted transactions are visible on block-explorer sites (in most cases)


  
  Is this unconfirmed and already dropped from the blockchain network. 
  


It is unconfirmed, but not because already dropped, but because not yet broadcasted


  
  Transaction have some error to start with and never broadcasted on blockchain network? 
  


May be. Only sender knows the correct answer


  
  None of the above and have some other issue?
  


If it is not seen - it does not exist. Point.