Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
>i have an old MS office 2011 on my computer that may be interfering with newly purchased MS 365
Which version of Office are you using now?
Do you install Office 2011 for Mac and Microsoft 365 apps together on your computer?
Please note, it is not recommended to install 2 versions of Office products with same apps on one computer. If you are using both of them, I suggest you uninstall Microsoft 365 apps first. (If you need to install Microsoft 365 apps, please refer to "This Article".)
Besides, do you find the "Activate By Phone" in the activation wizard as following small image when you activate Office 2011 for Mac?
If yes, please click Activate By Phone, and try to follow the instructions.

> ··· my email is already in use.
What version of Office is this email account associated with? Could you please share us with this error message?
In addition, please go to and sign your account into www.office.com, take a screenshot of Office shown on screen.
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