The first thing to say here is that the internet is your friend here, put the error code and message in a search engine and you will get answers!
When working on my own local Oracle server, I started getting the following when trying to start the listener:TNS-12535: TNS:operation timed out
TNS-12560: TNS:protocol adapter error
TNS-00505: Operation timed out
All the searching pointed to the listener.ora file but it was right and unchanged. It turned out that the hostname was not resolving properly, so adding it to the hosts file and pointing it at 127.0.0.1 got everything working again!