magento/composer-root-update-plugin is locked to version 1.0.0 and an update of this package was not requested
It seems your are using unsupported composer version.
Check the current composer version with:
composer -V
The 1.0.0 version of magento/composer-root-update-plugin requires composer-plugin-api ^1.0, so it's not compatible with Composer2. You can check out repository in more detail here.
If you just recently updated the composer you can run a rollback
composer self-update --rollback
Or install the latest release of version 1:
composer self-update --1
If you are updating Magento please check out the official documentation.
Hope this helps!
I was struggling with the same error recently. I downgraded composer to 1.9 and delete my composer.lock-file, it resolved that error you are having.
Downgrade composer:
- Uninstall composer
- Follow the instructions here: https://getcomposer.org/download/ with the excetion of using the download link for 1.9.3 (https://getcomposer.org/download/1.9.3/composer.phar)
Remove composer.lock file:
There is a file called composer.lock in your magento root folder. Delete it or move it just in case.
Then just run the command you did before.