# Troubleshooting This is a list of common pitfalls on using Composer, and how to avoid them. ## General 1. When facing any kind of problems using Composer, be sure to **work with the latest version**. See [self-update](../03-cli.md#self-update) for details. 2. Ensure you're **installing vendors straight from your `composer.json`** via `rm -rf vendor && composer update -v` when troubleshooting, excluding any possible interferences with existing vendor installations or `composer.lock` entries. ## Package not found 1. Double-check you **don't have typos** in your `composer.json` or repository branches and tag names. 2. Be sure to **set the right [minimum-stability](../04-schema.md#minimum-stability)**. To get started or be sure this is no issue, set `minimum-stability` to "dev". 3. Packages **not coming from [Packagist](http://packagist.org/)** should always be **defined in the root package** (the package depending on all vendors). 4. Use the **same vendor and package name** throughout all branches and tags of your repository, especially when maintaining a third party fork and using `replace`. ## Memory limit errors If composer shows memory errors on some commands: PHP Fatal error: Allowed memory size of XXXXXX bytes exhausted <...> The `memory_limit` ini value should be increased. > **Note:** Composer internally increases the memory_limit to 512M. > It is a good idea to create an issue for composer if you get memory errors. Get current value: php -r "echo ini_get('memory_limit').PHP_EOL;" Increase limit with `php.ini` for a `CLI SAPI` (ex. `/etc/php5/cli/php.ini` for Debian-like systems): ; Use -1 for unlimited or define explicit value like 512M memory_limit = -1 Or with command line arguments: php -d memory_limit=-1 composer.phar <...>