Hello. As soon as I open photoshop, version37.9.1, even without opening a particular photo, the following message is displayed: "A required view could not be created, because the definition file is missing or corrupted". What to do?

Try resetting the tools and/or preferences.

To restore preferences quickly using a keyboard shortcut:

Press and hold Alt+Control+Shift (Windows) or Option+Command+Shift (Mac OS) as you start Photoshop. You are prompted to delete the current settings. The new preferences files are created the next time you start Photoshop.

Note: Using the keyboard shortcut, preference files for custom shortcuts, workspaces, and color settings will also be reset to default.

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

you mean ps 27.9.1?

and copy and paste a screenshot of the error message into a reply here.