CS3 No longer able to CTRL+E for merging down layers?

[Agent 505]

I am not a graphic artist by any means but I frequently have been using CS3 for small projects.  Tonight I discovered that the program is no longer able to use CTRL+E for merging down layers, which I use that hotkey pretty much all the time.  Now it's suddenly not working?  Can anyone explain how to restore that functionality?  As far as I know I don't know how I could have simply deleted the option, as I only learned how to remap the keyboard shortcuts after the functionality vanished.

[c.pfaffenbichler]

What are the image’s Color Mode and bit depth? 

What have you done for all-purpose trouble-shooting so far? 

Restoring Preferences after making sure all customized presets like Actions, Patterns, Brushes etc. have been saved might be a good starting point:

https://helpx.adobe.com/photoshop/using/preferences.html

https://helpx.adobe.com/photoshop/kb/basic-trouble-shooting-steps.html

[jane-e]

@Agent 505 

In addition to what CP said, do not try uninstall/reinstall. The activation servers for CS3 were shut down several years ago and you will never be able to reactivate.

Can you merge the selected layers from the Layers panel menu?

Ctrl+E is "merge layers" when multiple layers are selected and "merge down" when one layer is selected.

Test in a new document with something simple to see if it's an issue with Ctrl+E or those particular layers. 

Jane