JavaScript29 errors documented

Common JavaScript Errors and How to Fix Them

Browse all documented JavaScript errors with detailed explanations, root causes, and step-by-step fixes.

Unexpected token ILLEGAL (while parsing file: script.js, line: 3)

This error occurs when JavaScript encounters an unexpected character or token in the code, which is not a part of the va

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Template is not a function. Got function for type: 'object'

This error occurs when a template function in a framework like React or Vue is called incorrectly. It happens when a com

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Unexpected token ILLEGAL, expected }

This error occurs when the JavaScript interpreter encounters an invalid or unexpected token in the code. In this case, i

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Error: Mongoose connection is not established before the query is executed

This error occurs when a Mongoose model is used to query the database before the connection to the database is establish

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MongooseError: Operation `users.updateOne()` buffering timed out after 30000ms d

This error occurs when a MongoDB update operation times out due to an ongoing write lock, preventing the update from com

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Missing required peer dependency 'express' for '@nestjs/core'. You must install

This error occurs when a required peer dependency is missing from the project, preventing the application from running p

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Error: ECONNRESET: Connection was reset

This error occurs when a connection to a database or a server is unexpectedly dropped. It can be caused by a network iss

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Unexpected token import in /path/to/script.js on line 1

A syntax error occurs when the JavaScript interpreter encounters a statement or expression that doesn't follow the langu

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Error: Unable to resolve dependency 'http-proxy-middleware' in /node_modules/rea

This error occurs when the dependencies of a project are not properly configured, and the framework is unable to resolve

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ReferenceError: Cannot access 'length' property on 'NaN' (while parsing at 'inpu

This error occurs when trying to access a property (like 'length') on a value that is not an object.

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ReferenceError: Cannot access 'x' before initialization

This error occurs when you try to use a variable before it has been declared or initialized.

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Error: Unable to resolve component 'MyComponent' from 'src/components/MyComponen

This error occurs when React is unable to locate the component file it's trying to render. It's often caused by a typo i

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