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Log into your MailUp Developer Console and navigate to the "Developer" page. You can now request your MailUp API keys by pressing "+" button and filling out the form.
You wil be asked to fill out a brief form.
Press the "Request Keys" button. Your request will be processed and your application will be available in the "Integrations" page (Account Settings > Developer's Corner > Integrations). There you will be able to access your API access keys, as shown in the screenshot below.
Publish your application to the MailUp Integrations catalog
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