I use a Mac and I have litecoin core on another machine and it will not open. I have installed litecoin core on another Mac and now I need to install the backup wallet.dat file from my other machine. I need help because I cannot find instructions on how to do this.
open up finder
type in ~/Library/Application Support/Litecoin/
copy the wallet.dat file and put it on a usb stick. take that usb and put on the new computer and paste in the same location (overwrite the existing or delete that one already there) and your wallet should open as normal. You may need new passphrase to encrypt the new core on the new mac.
Please note that all the files in this /litecoin folder work on mac or windows even the blockchain