Sometimes when I saved a sheet from Excel on a Windows or Mac OSX computer as a tab-delimited file for further data processing, I frequently encountered the annoying ‘^M’ issues. To save my own time and to help the others who have the same issues, here are the solutions:
Install SSH Server
sudo apt-get update && sudo apt-get upgrade && sudo apt-get install openssh-server
By putting your public key on the remote servers, one can connect to them without passwords, the pairing private key on your local client will do the authentication work.