I lost my Windows 8 product key. How do I get the key information?

First retrieve your key on the computer where its installed.

Here are four utilities, all of which will may display your product keys if they are still there:
Belarc Advisor: http://www.belarc.com/free_download.html
(It does a good job of providing a wealth of information.)

Also: http://www.magicaljellybean.com/keyfinder.shtml
and: http://www.nirsoft.net/utils/product_cd_key_viewer.html
and RockXP: http://www.majorgeeks.com/download4138.html which has additional features

or

Go to the order summary page, there you will find your product key:

https://www.mswos.com/

then

Press Windows key + X

Click Command Prompt (Admin)

Click Run as administrator
At the command prompt, type: slmgr.vbs -upk

Hit Enter, this will uninstall the product key from the computer and set it back to trial mode, you are now free to use it on another computer.

You can reactivate by telephone:

You can't "migrate" Office with  Windows.

You install Windows on the new computer, then you install Office 2013 on the new computer from your original install media.

You can't "migrate" Office with  Windows.

You install Windows on the new computer, then you install Office 2013 on the new computer from your original install media.

 

So you didn't save a copy of the downloaded file to external media?

Log back into the account from which you originally downloaded it, download the installer file AND BURN OR COPY IT TO A DISK OR EXTERNAL MEDIA!!!!!! (Write the Product key on the disk or in a text file and keep the lot in a safe place)

I have to say I am at a loss why people don't do this as a matter of course after spending a lot of money - makes no sense to me at all.

>So you didn't save a copy of the downloaded file to external media?

Yes I did, and I have a product ID for the software as well. The file is only 546kb in size. I need to know whether that copy of Office is attached to a specific computer, a specific operating system instance, and transferring it to another computer will break the agreement.

 The file is only 546kb in size.

That's not an Office installer file. The Office install file should be somewhere in the region of a Gigabyte....

Log back into the account and re-download it.