Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires enlightn/security-checker ^1.10 -> satisfiable by enlightn/security-checker[v1.10.0, v1.11.0]. - enlightn/security-checker[v1.10.0, ..., v1.11.0] require guzzlehttp/guzzle ^6.3|^7.0 -> found guzzlehttp/guzzle[6.3.0, ..., 6.5.8, 7.0.0, ..., 7.15.3] but it conflicts with your root composer.json require (^8.0.0). Use the option --with-all-dependencies (-W) to allow upgrades, downgrades and removals for packages currently locked to specific versions.