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- Open the start menu
- search cmd
- open the command prompt application
- type "systeminfo" (without quotes) and hit the enter key.
Windows 8
1 - Go to the Search Charm How to Search in Windows 8
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Mac OS X Mountain Lion (10.8)
- Open the console window in the Utilities folder, as outlined above.
- Navigate to /var/log, then click on install.log
- Scroll all the way to the top of the list, until you see a series of text that says "Install Mac OS X Mountain Lion"
- The date next to the text is the install date.
Mac OS X Yosemite and El Captain (10.10 & 10.11)
- Open the console window in the Utilities folder, as outlined above.
- Navigate to /var/log, then click on install.log
- Scroll all the way to the top of the list, until you see a series of text that says "OSInstaller"
- The date next to the text is the install date.
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