# TS2503: Cannot find namespace '…'.

> A qualified type name like A.B refers to a namespace that doesn't exist. Import the namespace or fix its name.

## What it means

In a type position, `Name.Member` looks `Name` up as a namespace. When no namespace (or
namespace import, or enum) with that name is in scope, it is reported. Missing `@types`
packages that provide global namespaces such as `NodeJS` or `React` are a common cause.

## Example

```ts
export let timer: Timers.Handle;
```

## How to fix

- Fix the spelling, or import the namespace: `import type * as Timers from "./timers"`.
- For global namespaces from type packages, install the package and add it to `types` in tsconfig if you list them.

Source: https://ts-r.dev/errors/TS2503/