1. ERROR The Personal Access Token is mandatory The error message "ERROR The Personal Access Token is mandatory" means that you're trying to perform an operation (most likely publishing a VS Code extension using vsce) that requires authentication with the VS Code Marketplace, and you haven't provided a Personal Access Token (PAT). Here's a breakdown of the problem and how to fix it: Understanding the Error Authentication: Publishing extensions to the VS Code Marketplace requires authentication to verify your identity and permissions. This authentication is done using a Personal Access Token (PAT). vsce Requirement: The vsce (Visual Studio Code Extensions) tool, which is used to package and publish VS Code extensions, requires a PAT to authenticate with the marketplace. Missing PAT: The error indicates that you're running a vsce command (like vsce publish) without providing a PAT. 2. How to Fix the Error Create a Personal Access Token (PAT): You'll need to create a PAT on Azure DevOps (formerly Visual Studio Team Services), which is used to manage VS Code Marketplace authentication. Follow these steps: Go to your Azure DevOps organization. Click on your user settings (usually your profile picture) in the top right corner. Select "Personal access tokens." Click "New Token." Give your token a descriptive name (e.g., "VS Code Extension Publishing"). Set an expiration date for the token. Under "Scopes," select "Marketplace (Publish)." This is the crucial step. Click "Create." 3. Important: Copy the generated PAT immediately and store it securely. You won't be able to retrieve it later. Provide the PAT to vsce: You can provide the PAT to vsce in a few ways: Environment Variable: The recommended approach is to set the VSCE_ACCESS_TOKEN environment variable. Windows: Bash setx VSCE_ACCESS_TOKEN "your-personal-access-token" After setting the environment variable, close and reopen your terminal. macOS/Linux: Bash export VSCE_ACCESS_TOKEN="your-personal-access-token" If you want to make this change permanent, add the export command to your shell's configuration file (e.g., ~/.bashrc, ~/.zshrc). Command-Line Argument: You can provide the PAT as a command-line argument using the --pat flag: Bash vsce publish --pat "your-personal-access-token" This is generally less secure than using an environment variable, as the PAT will be visible in your command history.