Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires maatwebsite/excel ~3.1.56 -> satisfiable by maatwebsite/excel[3.1.56, 3.1.x-dev]. - Conclusion: don't install roave/security-advisories 9999999-dev (conflict analysis result) - Root composer.json requires roave/security-advisories * -> satisfiable by roave/security-advisories[dev-master, dev-latest].