Reinstalled with succes (impossible to repair). I first uninstalled then rebooted and reinstalled and rebooted. Before my message, I reinstalled without uninstalling and reboot.

That runs now. But I wonder why this file was not found. It was in system32 when the windows opened and a message said msvcr70.ddl was not found. Three days ago avast detected a trojan from a loaded game of my son. My son wasn’t able to cancel the infected file and I had to cancel it by themalware scanner a2 after hours. Can a trojan desactive avast ?