Hi LBH, terryn, thanks for your answers.
Are you sure you have the correct settings in Preferences and have installed your plug-in in the correct folder?
Yes. You say "installed" ? I just move the .dll in the folder.
Hi after installing Al3 make sure you rescan in ableton the vst or AU.
And yes, I have verified that folder are correct, and I rescaned in ableton.
When I installed Analog 3, I found the folder in Program files (x86) : "Vst Plugins" and I found "Analog Lab 3.dll" maybe it isn't this file to put in Ableton VST folder ?
Thanks again !