Lets say you are trying to create an SSH tunnel.
ssh -L 27017:somehost:27017 email@example.com
You may get the following error message.
ssh: Error resolving hostname \342\200\223L: nodename nor servname provided, or not known
This is caused by using the wrong kind of minus symbol. If you have copied and pasted the command from somewhere, this is probably the case. This is easy to fix – simply paste the command into your terminal, then go through it, remove the existing minus symbol and put a new – in.