I’ve had a problem on a few older projects where composer dies with “????%” after running
composer update. The problem is that the PHP version is too old, usually a version of 5.3.x, and can’t handle unicode correctly. So if you are seeing the following:
composer update ????%
The fix for PHP Composer “????%” issue is:
composer -ddetect_unicode=Off update
Of course, the better solution would be to upgrade your PHP version.
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