🚨 Pulumi Error: 'unknown resource type aws:s3/bucketv2:BucketV2' — Cause, Fix, and Troubleshooting Guide

Overview

error: unknown resource type 'aws:s3/bucketv2:BucketV2' means the Pulumi engine asked a provider plugin to create a resource, but that provider does not recognize the resource token you used. A resource token has the form <package>:<module>/<type>:<Type> (for example aws:s3/bucketV2:BucketV2). The engine routes the request to the aws provider plugin, and the plugin looks the token up in its schema. If it is not there, you get this error.

error: unknown resource type 'aws:s3/bucketv2:BucketV2'

There are two flavors of this problem. Either the token is wrong (a typo, wrong casing, or a renamed/removed resource), or the installed provider version does not define that token (too old, too new, or a version drift between your SDK and the plugin). Note that tokens are case-sensitive: bucketv2 is not the same as bucketV2.

Symptoms

• pulumi up or pulumi preview fails with unknown resource type '<package>:<module>/<type>:<Type>'.
• You recently upgraded or downgraded a provider SDK, or bumped a plugin version.
• You are hand-writing YAML or using dynamic/token-based construction and mistyped the token.
• The resource works for a teammate on a different provider version.

Common Root Causes

1. Wrong casing or a typo in the token

Tokens are case-sensitive. aws:s3/bucketv2:BucketV2 (lowercase v) is not the same token as aws:s3/bucketV2:BucketV2. A single wrong character makes the token unknown.

2. Provider version too old to define the resource

The resource was added in a newer provider release than the plugin you have installed. For example BucketV2 requires a recent aws provider; an old plugin has never heard of it.

pulumi plugin ls

3. Resource renamed or removed across a major version

A provider major upgrade renamed or dropped a token. Code written against v5 may reference a token that v6 restructured, or vice versa.

4. SDK and plugin version drift

Your language SDK (npm/pip/go module) and the installed resource plugin are out of sync, so the SDK emits a token the installed plugin does not implement.

5. Wrong package name entirely (classic vs native / community provider)

Using a token from a different package — for example an azure-native token while only the classic azure plugin is installed, or a community provider that was never installed.

How to Diagnose

Confirm exactly which providers and versions are installed:

pulumi plugin ls

Compare that to the SDK version your program depends on (for TypeScript/Node):

npm ls @pulumi/aws

For Python or Go, check requirements.txt / go.mod respectively. Then verify the correct token in the provider’s API docs, and double-check casing character by character. A preview will confirm whether fixing the token or the plugin resolves it:

pulumi preview

Fixes

Correct the resource token / constructor. Prefer the SDK’s typed constructor over hand-written tokens so the compiler catches mistakes. The correct S3 v2 bucket is aws.s3.BucketV2:

// Correct casing and type
const bucket = new aws.s3.BucketV2("web", {});

If you must reference the raw token (YAML or dynamic code), use the exact case from the docs — aws:s3/bucketV2:BucketV2.

Upgrade the provider plugin to a version that defines the token. Install the plugin version that includes the resource, then retry:

pulumi plugin install resource aws 6.42.0
pulumi up

Pin the provider version in your project so plugin and SDK match. For TypeScript, pin the SDK in package.json and reinstall:

"dependencies": {
  "@pulumi/aws": "6.42.0"
}

npm install

For Python, pin it in requirements.txt (pulumi-aws==6.42.0) and pip install -r requirements.txt. You can also pin the plugin declaratively in Pulumi.yaml:

plugins:
  providers:
    - name: aws
      version: 6.42.0

Install a missing community/native provider. If the token belongs to a package you never installed, add its plugin:

pulumi plugin install resource azure-native 2.50.0

Remove and reinstall a corrupted plugin. If versions look right but the token is still unknown, clear and reinstall the plugin:

pulumi plugin rm resource aws --all --yes
pulumi plugin install resource aws 6.42.0

What to Watch Out For

• Resource tokens are case-sensitive — bucketV2 and bucketv2 are different tokens.
• Keep the SDK and plugin versions aligned; drift between them is the most common cause after typos.
• Read provider release notes before major upgrades — tokens are occasionally renamed or removed (e.g. classic Bucket vs BucketV2).
• Use the strongly typed SDK constructors instead of raw tokens wherever possible so your compiler/linter flags unknown types before pulumi up.
• Pin provider versions in Pulumi.yaml, package.json, or requirements.txt so CI installs the same plugin that defines the tokens your code uses.

Related Guides

• Pulumi Error: ‘could not load plugin’ — Troubleshooting Guide
• Pulumi Error: ‘failed to register new resource’ — Troubleshooting Guide
• Pulumi Error: ‘Duplicate resource URN’ — Troubleshooting Guide