Here is a quick and easy way to find out the date and time at which your PC operating system installed (or last upgraded). Open the command prompt (start-> run -> type cmd-> hit enter) and run the following command systeminfo | find /i "install date" In couple of seconds you will see the installation dateFind Windows 10 Original Install Date and Time using WMIC Command 1 Open a command prompt. 2 Copy and paste the command below into the command prompt, and press Enter. (see screenshot below) wmic os get installdate
How do I find the date and time of an installation?
Using the Windows Registry The Windows installation date and time is stored in the following registry key in the values named InstallDate and InstallTime: The InstallDate value data contains the Unix time which represents the number of seconds that have elapsed since 1970-01-01T00:00:00Z (January 1, 1970, at 12:00 AM UTC).
What is the format of installinstalldate?
InstallDate is in the UTC format (yyyymmddHHMMSS.xxxxxx±UUU) as per Microsoft TechNet article "Working with Dates and Times using WMI" where notably xxxxxx is milliseconds and ±UUU is number of minutes different from Greenwich Mean Time.
What does the “installdate” result mean?
A single “InstallDate” result will be returned with a string of digits. These digits represent the Windows installation date in the format YYYYMMDDHHMMSS, with time displayed in 24 hours. In our example, 20130909181058 equates to September 9, 2013 at 18:10:58 (or 6:10:58 PM), the exact same time that was reported by the SystemInfo command.
How to find Windows 10 original install date and time using WMIC?
Find Windows 10 Original Install Date and Time using WMIC Command 1 Open a command prompt. 2 Copy and paste the command below into the command prompt, and press Enter. (see screenshot below) wmic os get installdate

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