Hello
I have a problem for a while with the ALT key and left mouse click to select around a cube for example, normally you hold the ALT key and LMB click near the stop in the direction you want to go and all the tour is selected normally, but it does not work!
I know it’s not the ALT key on the keyboard because I tested it and tried with 5 different mice it’s the same.
I have the last version of blender , and i try also on the lasted version and is same problem !
Thank for your help
Alt is a modifier key that can be used by Operating System shortcuts to manage its windows or menus or…
So, there can be conflicts with default Blender keymap.
That being said, Alt + LMB click in object mode is showing a Select Menu ; when you click on overlapping objects according to point of view.
I am not sure if that is what you meant, or if you are confusing default with an addon shortcut or one of numerous keymap preferences using Alt key.
Please explain with an image.
I’m not sure exactly what the problem is (maybe it’s a language issue 
)
Alt + LMB is used to select connected edges in edit mode. Is this the problem?
※ If you can’t attach an image, just participate a little bit in the community and you will be granted the ability to attach files. 
not at all you had to change the parameters of your attributions
Sorry i just reply ! sorry for the confusion of the message if there is any ! it’s the first time that I use this forum
The function is Ctrl+Alt+LMB.
This is the default setting, and you need to modify the keymap to change it.
※ Copy and use the settings when adding or changing keymaps.
That way, it will be easier to return to the default values when there is a problem.
You can replicate by pressing + next to the blender at the top.
Thank so mucht It was that …
