A family of Microsoft word processing software products for creating web, email, and print documents.
You asked about "upgrade". That is no longer. Office 2010 was the last version that had the "valued customer" upgrade discount.
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MS only sells Office 2021, and 365. There is no "upgrade discount" so no need to prove you had the older version.
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If you are trying to install 2007 on the new computer to continue using it, you are in for an interesting time.
Borrow a computer that has a CD/DVD drive, copy all of the files to a USB drive, or to OneDrive.
Then copy the install files to the local drive before running the install.
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MS is making it difficult for users to install unsupported versions. They push out various error messages. Some that you can get around, and at least 1 that is a dead end. If you get the message you have it installed on too many machines, you are out of luck. There is nothing anyone can do for you.
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