Stardock Forums
I have seen this on the web: If you have already purchased the upgrade and have the new license key, on the 'Primary' Multiplicity PC, in the Multiplicity configuration menu, go to 'About', 'Change License', then 'Update Product Key'.However, I don't have the 'Change License' tab. Please help. Thanks!
Hello,
Sorry to hear you are having issues. I believe you also can do this. Deactivate multiplicity using this guide: https://forums.stardock.com/486311/accounts-and-activation-support-faq#deactivateproduct. Than close and open again Multiplicity. When ask for activation, enter your new key.
Thank you.
Basj,
Stardock Community Assistant.
Thanks for the reply. Here's what I see: 
As you can see, I don't have a tab to deactivate Multiplicity. I have installed the product again, but never get the option to enter a key. Please help. Thanks!
Go to your account page https://store.stardock.com/myaccount/products
Click on your Login Avatar in the top right corner of the page and select downloads. Now find the Multiplicity listing and click the three dots. You should see your activations and the option to Deactivate an install.
Hope this helps.
Success! After a second uninstall/reinstall reboot, I was able to enter my new upgrade code. Thanks for your help, and have a great day!
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