This message show up when I'm trying to go into catalog/manage product:
Fatal error: require_once(): Failed opening required 'Mage/Adminhtml/Block/Catalog/Product/Grid.php' (include_path='/home/hoon/public_html/includes/src:.:/usr/local/php56/pear') in /home/hoon/public_html/includes/src/SSTech_Categorygridfilter_Block_Adminhtml_Catalog_Product_Grid.php on line 3
When I disable the compilation status everything is ok.
Kindly note that I used megeworks to import categories.