Photoshop ctrl+z not working and Undo option in menu greyed out

[Rei-Bob]

I've been using photoshop for over an hour and ctrl+z was working - until it wasn't. It stopped working and the undo option in the edit menu is greyed out and not selectable. I have to use history to undo. How do I get them back?! I use ctrl+z a LOT. 

[Kevin Stohlmeyer · Accepted solution]

Have you saved and restarted Photoshop?

If that didnt resolve, go to your preferences and click the Reset Preferences upon Restart button in the General Section.

Restart your PS and see if that does the trick.

[Rei-Bob]

I will try the preference reset! Thank you 

[Rei-Bob]

My preferences menu is also greyed out and not selectable 

[Rei-Bob]

Ok resetting preferences seems to have worked 

[Rei-Bob]

I restarted PS and the preferences option came back. I reset preferences and now ctrl+z is working again.

[Rei-Bob]

I've already closed photoshop and reopened it - it didn't help