andre_debian@... composed on 2015-08-16 23:40 (UTC+0200):

> Yes, the mouse works fine on another Linux Wheezy,
> with kde-trinity 3.5 : I can resize the windows.

What is it you are using now, Jessie?

> How to reinstall kde -trinity 3.5 ? Which commands ?
> I think that it is not properly installed...

Maybe it's not Trinity but the driver not (properly) installed. Do you have
both xserver-xorg-input-evdev and xserver-xorg-input-mouse installed? Maybe
the solution is to force a switch from the one in use (according to
Xorg.0.log) to the other. Jessie is probably using evdev as here, Wheezy more
likely mouse.
-- 
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words are persuasive." Proverbs 16:21 (New Living Translation)

 Team OS/2 ** Reg. Linux User #211409 ** a11y rocks!

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