Hi @Saeid Rajabzadeh
As Q&A forum is a public place, to protect your private information, I would delete some information in your post.
Thanks for your understandings.
For your issue, can you contact the seller to verify whether Office 2016 Professional Plus is a retail or volume licensed version (Probably not very probabilistic)?
- If it is a retail version, please refer to Jordan M's suggestions. As the license is bound with your Microsoft account, and you can install Office Professional Plus from Services & subscriptions webpage.
Another way, please refer to Psirontech's sharing in thread "Download ISO file for Office Professional PLUS 2016". But, to activate the Office, you still need to sign into the licensed account.
- But if it is volume licensed version, the installation file needs to be download from VLSC, and it needs Admin's account to sign in.
Hope the information could be helpful to you.
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