I was wondering how to know the installation date of my current Windows OS. I goggled it and found out a dos command which is very useful for finding system information. To know the installation date of windows, command is as follows
Go to Run–>Cmd and then type
systeminfo | find /i “install date”
And if you want to find out the last time when you booted your PC then go to cmd and type
systeminfo | find /i “boot time”
This will show the time when you last rebooted the computer.
Alternative, you could start Windows Task Manager (Alt+Ctrl+Del), switch to the Performance tab and you should see a field that says “Up Time” that’s even more convenient but some computers have Task managers disabled.