Illustrator CC update

I've seen Illustrator CC automatically update recently and the programme will now no longer open up when clicking the shortcut, the app in the programme list OR via the creative cloud app. The programme appears to start as the cursor goes to a 'swirly blue' circle than disappears completely and nothing happens. 

Task manager shows no app running but in background processes you see Illustrator 2021 with 0% CPU and 13.4% memory being used. If I do not 'end' that task, any further action, such as going backwards to an older version of illustrator CC, will not start and I get a message asking for me to close Illustrator. Clearly I dont see Illustartor as being open so something is clearly wrong somewhere? Incidentally, the previous update delivered me a message that said there was an issue with my graphics card which needed an updated driver. Did all of that and the message still kept coming up but I saw an option to continue anyway which I did and all was happy again. 

This is stopping me functioning really so has anyone got any ideas as to what to do? Any help/guidence would be appreciated.

Thanks...