Laptop hangs on KDE Plasma login screen after update

I just updated my i7 TW KDE laptop this afternoon and now when I reboot it (which was required after update) it hangs on the KDE login screen. I can input my password which seems to be accepted but nothing else happens. I can ctrl/alt/f2 for a new console login which works but I’m at a loss to know where to go next to determine why the main Plasma login is hanging and the HDD light does not appear to be flashing so no HDD access seemingly.

Can anyone please suggest where to go from here?

Stuart

Well this morning I decided to boot up the laptop and when it hung I could try a few things from the console window. However this morning it booted up with no problem at all!!! Why it hung last night when I booted it several times I have no idea. Anyway right now it is working. Obviously the gremlins ahve gone away at least for now!

Stuart