I am not programmer, but web designer, once I made magento e-store with success.
Now I have problem with products display. They are not visible in Categories, but if I search for SKU or product name, they display, but if I click on it, there is empty page opening
HTTP ERROR 500
I have searched for solutions without success, and of course, all main settings are correct (visible, in stock, amount, correct category etc.) I use magento 1.9 and my site is with 3 languages (works ok)