
Hi @431Lunchbox
Does this Office is volume licensed version or retail version?
1. If it is volume licensed one, you can contact your administrator to get the installation package, or you can find the installation package from other people.
Then, for volumn licensed versions, the client can connect to KMS Server or use MAK key to activate Office. For details, it's recommended to contact your administrator.
2. If your Office Professional Plus 2013 is retail version, I suggest you login your Microsoft Account into https://account.microsoft.com/services, check whether there is Office Professional Plus 2013 listed.
If yes, you can install Office from this webpage.
Or you can refer to "Create an Office 2013, 2016 and 365 Offline Installer with the Office Deployment Tool", use ODT to install Office 2013, but to activate Office, you still need to sign licensed Microsoft Account into Office.
(Please Note: Since the web site is not hosted by Microsoft, the link may changed without notice. Microsoft does not guarantee the accuracy of this information.)
Besides, this Microsoft Account is the one bound with your Office key. Besides, if you have activation issue, you need to contact Microsoft to seek help.
Hope the information is helpful to you.
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