Composer version issue

saosangmo

Hello,
When I try upgrade, i get this message and my forum is down now. Please help me.

Fatal error: Class UpdateHelper\ComposerPlugin contains 2 abstract methods and must therefore be declared abstract or implement the remaining methods (Composer\Plugin\PluginInterface::deactivate, Composer\Plugin\PluginInterface::uninstall) in /home/xxx/public_html/vendor/kylekatarnls/update-helper/src/UpdateHelper/ComposerPlugin.php on line 11

luceos

What is the output of

composer -V

saosangmo

luceos I get the same error when run your command.

luceos

Sounds like you installed a broken second version of composer. Try to install the stable version 1.

saosangmo

luceos I am so sorry, I get this output
Composer version 2.0.0-alpha2 2020-06-24 21:36:18
Please help me.

luceos

saosangmo if you can still run composer commands, run this:

composer selfupdate --stable

saosangmo

luceos after I remove the vendor folder and run composer install again.

saosangmo

I run your command, but I got this message:

  [Symfony\Component\Console\Exception\CommandNotFoundException]
  Command "selfupdate" is not defined.

luceos

What's the output of composer list?