For Switzerland use one of the NTP pool servers as listed under
To configure your Windows system to get the time and act as a time server run following commands using one of the listed timeservers.
There is no need to list multiple servers as the Pool is already a list of about 4 servers.
net stop w32time
w32tm /config /syncfromflags:manual /manualpeerlist:2.ch.pool.ntp.org
w32tm /config /reliable:yes
net start w32time
w32tm /query /status