@ bing: Thank You for Your support.
I didn’t understood the whole site location thing, but after looking at URL You gave me, I tried to update eclipse with
Name: System Workbench for STM32 - Bare Machine edition
In this special case, I have a different error and it is the following:
An error occurred during the org.eclipse.equinox.internal.p2.engine.phases.CheckTrust phase.
session context was:(profile=epp.package.cpp, phase=org.eclipse.equinox.internal.p2.engine.phases.CheckTrust, operand=, action=).
Error reading signed content.
Exception in opening zip file: C:\eclipse\plugins\fr.ac6.mcu.debug_18.104.22.168612060912
After all, I didn’t found a work around.