To upgrade your Indigo 3 licence to an Indigo 4 licence, follow these steps:
When you purchased an Indigo 3 licence, you will have received an email from firstname.lastname@example.org, which contains a link to your private licence page on store.glaretechnologies.com.
If you can't find the email, please contact email@example.com for assistance.
Please follow this link to go to your licence page.
Then click on the "Buy Now" button in the "Upgrade to Indigo 4" section.
Upon clicking the "Buy Now" button, you will be taken to an order summary page for your upgrade order, which will summarise the cost and allow you to select the payment method to complete the order.