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Activation Guide v2.1.0

Activate Letterblack and add your API key correctly.

This guide walks users through the full first-time setup: buying the extension, installing it, activating the license, and adding the AI API key inside the panel so Letterblack can start working.

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1

Buy and download

Purchase Letterblack from Gumroad, then download the installer or extension package from the order page or purchase email.

Use the same email and purchase details from Gumroad during activation.
2

Install in After Effects

Run the installer or complete the manual extension install, then restart After Effects if it was already open.

  • Open After Effects
  • Launch the Letterblack panel from the extension menu
  • Wait for the first setup screen to load
3

Activate your license

On first launch, use the activation or license screen inside the Letterblack panel. Enter the Gumroad purchase information exactly as provided.

  • Paste the license key or activation value from Gumroad
  • Complete the activation check in the panel
  • Wait for the panel to confirm activation before moving on
4

Where to place the API key

After activation, open the settings area inside the Letterblack panel and go to the AI or provider configuration section.

  • Open Settings inside Letterblack
  • Find the API Key or Provider setup field
  • Paste your OpenAI, Claude, Gemini, or supported provider key there
  • Save the key, then run a small test prompt to confirm the connection
Place the API key inside the Letterblack panel settings, not inside After Effects preferences.

If activation does not work

Double-check the Gumroad purchase details, make sure the panel is updated, and restart After Effects before retrying activation.

If the API key does not work

Confirm the key is active with your provider, paste it without extra spaces, save it in Letterblack settings, and test again from the panel.