The last Sony let me create restore media. If you elected not to, well you can first backup your stuff a few times and try the onboard restore methods. Windows 8 native methods are on the web and your Sony may use that.
There is new malware that does this. I've yet to get a workaround to avoid the reload or reset.
Link to follow,
Bob
https://www.google.com/#q=windows+8+reset+to+factory+sony
Purchased a Sony Vaio e-series notebook 6/2013 new with Windows 8 and using Explorer. This week it suddenly put up a "Windows Activation" screen asking for the key number or to insert the CD. It gives the last 6 characters of the current key code. At times can still access internet but its slow. Obviously do not have a CD or key code as it came pre-installed when new. Anyone with a similar problem or fix?'
Thxs

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