It locks the computer
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If I understand the question correctly, you are describing the malfunction of two specific keys on your keyboard. If this is the case, you probably need to replace the keyboard. The two keys work 100% fine in other shortcuts and in single use. its just this one shortcut.
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The keyboard shortcuts for text alignment on a Windows PC are: Control plus L for left alignment. Control plus R for right alignment. Control plus E for centre alignment. For Excel the shortcuts are below:
It does nothing. Pressing CTRL and the + sign zooms in your screen though
The keyboard shortcut notation ctrl plus esc means you press the Control key concurrently with the Escape key. On a Windows PC, the Ctrl + Esc shortcut produces the Start Menu.
Usually, it is the shortcut to save the document. EG: save as
The action assigned to shortcut keys can be different in different applications. In the case of Microsoft Excel, Ctrl+1 is a useful shortcut to the format dialog, where you can assign cell formats, borders, etc.
The words in the screen turn blue
Yes. It is not deleted, but will go to the clipboard and could be pasted elsewhere.
Alt+F4 is an almost universal shortcut in many platforms to exit or quit the application.