Hello !
i add many times a user in a AD security group, but the user is removed automatically after a day. What i don't understand is that other users have been added to the same group but they are still in the group (there is no problem with their accounts).
To add this user that is always removed after a day (or a period), i use the member of tab in the account properties.
Right click on the user account -> properties-> member of -> add -> groupName->ok
Thank you for your help !!