I get this

Warning: require_once(E:\WebSites\frostbr.co.uk v.5.6.2.1\Html\updates\concrete5.6.2.1\concrete/models/json.php): failed to open stream: No such file or directory in E:\WebSites\frostbr.co.uk v.5.6.2.1\Html\updates\concrete5.6.2.1\concrete\core\libraries\loader.php on line 48

Fatal error: require_once(): Failed opening required 'E:\WebSites\frostbr.co.uk v.5.6.2.1\Html\updates\concrete5.6.2.1\concrete/models/json.php' (include_path='E:\WebSites\frostbr.co.uk v.5.6.2.1\Html/libraries/3rdparty;E:\WebSites\frostbr.co.uk v.5.6.2.1\Html\updates\concrete5.6.2.1\concrete/libraries/3rdparty;.;C:\php\pear') in E:\WebSites\frostbr.co.uk v.5.6.2.1\Html\updates\concrete5.6.2.1\concrete\core\libraries\loader.php on line 48

I think it's something to do with some 3rd party block I've got. I think there is a twitter feed on the page. Could that be the cause?

Thanks