Yes, I did read your post. Bittrex sent me this a few days ago, showing the bitcoin address (receiving address for my Electrum BTC wallet) that I sent it to, is actually a valid litecoin address: http://ltc.blockr.io/address/info/3Mjr6FjR5T5Mc5rSRvKDhPxEYPfmmVzTXR

I was able to export the private key for that address, but can't figure out how to import it into any litecoin wallets, as the private key for this address doesn't seem to be recognized by any litecoin wallets, and won't let me move to the next step (any buttons are greyed out, etc.).

Bittrex escalated this and here's the reply I just received: Unfortunately, I have no clue how to help. It looks like you sent litecoin to a multisig BTC address which is valid on both networks. I don't know the process to recover the funds. You might try posting on the forums.

The litecoin was sent from Bittrex to my bitcoin wallet, and Bittrex told me that I just need to import my private key from my bitcoin address/wallet that I sent it to, to a litecoin wallet. The problem I'm having is that I'm following the instructions to import the private key into the wallet, but the litecoin wallets that I downloaded don't seen to recognize the private key. I checked the bitcoin address that the litecoin were sent to, and it looks like all the litecoins are still there, but I just can't figure out how to import the private key and retrieve them.

Thanks for the tip and assurance. I'm trying to do this by importing my private keys from my Electrum BTC wallet to my Electrum LTC wallet, using the sweep function, restoring the wallet, etc. but it doesn't seem by working and allowing me to move forward (for example the 'sweep' button is greyed out). I must be doing something wrong, and wonder if the Electrum LTC wallet isn't recognizing the keys from the Electrum BTC wallet? Thanks again for any help!

I didn't realize that Electrum had both a bitcoin and litecoin wallet, so I downloaded the wrong wallet (bitcoin instead of litecoin) and sent litecoin to it. What will happen? Is is possible to retrieve my litecoin or is it unretrievable? Thanks for any help!