Npm err! cannot read properties of undefined (reading ‘isstream’)

The error “cannot read properties of undefined (reading ‘isstream’)” occurs when the ‘isstream’ property is being accessed on an undefined object.

This error is commonly seen when using npm, and it usually indicates that there is a problem with the installation or configuration of a particular package.

To fix this error, you can try the following steps:

1. Clear npm cache: Run the following command in your terminal to clear the npm cache:

           npm cache clean --force
         

   This will clear the cache and may resolve any issues caused by cached data.

2. Update npm: Make sure you have the latest version of npm installed. Run the following command to update npm to the latest version:

           npm install -g npm
         

   This will update npm globally on your system.

3. Reinstall the package: If the error is specific to a certain package, you can try reinstalling it. Run the following command to uninstall and then reinstall the package:

           npm uninstall <package-name>
           npm install <package-name>
         

   Replace <package-name> with the actual name of the package you want to reinstall.

4. Check package.json: Ensure that the package.json file in your project’s root directory is properly configured. Make sure that all dependencies are listed correctly and that there are no syntax errors in the JSON file.

These steps should help you resolve the “cannot read properties of undefined (reading ‘isstream’)” error. If the error still persists, you may need to troubleshoot further or seek help from the package maintainer or the npm community.

Example:

    $ npm install isstream
    npm ERR! cannot read properties of undefined (reading 'isstream')
    ...
    $ npm cache clean --force
    ...
    $ npm install -g npm
    ...
    $ npm uninstall <package-name>
    ...
    $ npm install <package-name>
    ...