plugin doesn’t activate

Fatal error: require_once(): Failed opening required ‘C:\Projects\HMH\src\wp-content\plugins\ninja-forms/lib/NF_VersionSwitcher.php’ (include_path=’.;C:\php\pear’) in C:\Projects\HMH\src\wp-content\plugins\ninja-forms\ninja-forms.php on line 15 Call Stack: 0.0015 503416 1. {main}() C:\Projects\HMH\src\wp-admin\plugins.php:0 1.3611 42688720 2. plugin_sandbox_scrape() C:\Projects\HMH\src\wp-admin\plugins.php:164 1.3627 42807992 3. include(‘C:\Projects\HMH\src\wp-content\plugins\ninja-forms\ninja-forms.php’) C:\Projects\HMH\src\wp-admin\includes\plugin.php:1882