unable to execute the command, due to a program error

[bartoszs27125498]

Since yesterday. When I use the tools I get the message "unable to execute the command, due to a program error". I can't scale objects or use half of the functions. Do you know how to solve this problem?

[c.pfaffenbichler]

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