After moving from old Exchange Server 2013 to Microsoft Office 365 but migrated mailboxes does not work. Since I have license key for Microsoft Office 2013. I like to download the Microsoft Office 2013 to connect to mailbox, export it to PST and then import and upload to Office 365. Is there any way I can download Office 2013?
Mainstream support for Office 2013 ended almost four years ago, and extended support will end in just over a year. If you are in a paid support agreement with Microsoft, you can log into your Microsoft account, go to the section sign in to download Office.
Reference: Download and install or reinstall Office 2019, Office 2016, or Office 2013 > Office 2013 for PC