Lost prompt in Putty
 

As a (rather aged) newbie I have been successfully using Putty and Tightvnc to replicate my Raspberry Pi screen on my Win10 desktop.

Now, with no changes to the Putty configuration, Putty connects to my Raspberry Pi but without either a login or command prompt - only an upright green rectangle and will not accept any input. How can I get the prompt back? I have rebooted both machines but without any change to the Putty problem.

Can you ping the R.Pi by IP address? You could also do a port scan with nmap to see if there is a listening SSH server.

How can OP investigate what's running, without any console? [My Newbie 'HowTo...' LinuxQuestion!]
For example, if I 'broke' something, such that: sshd runs ok, but can't start/fork a shell (and just leaves the connection connected).
Do SingleBoardComputers have any way to have a console?

Lost prompt in Putty
 

Hi, ferrari,
thanks for your interest - however, problem solved in the simplest way. Although I had rebooted the Pi several times without success I was encouraged to reboot again just in case previous boot had, for some reason, not been complete.

So I rebooted Pi again and to my surprise the prompt was back and I could login and open Tightvnc successfully. Don't know what or how but shows that the simplest ways sometime solve the problem. Been in and out several times and all still working well.

Thanks again

Cool! WELCOME cwmwlyrallt to LQ! Great to hear of your "Pi"!
p.s. don't forget to mark this Thread as "Solved" (Thread Tools, at top).

Thanks for the update.