Blank page after config new products

Hello, I use version 4.02 and after installation everything was going great.

I did some modifications to backend and the site was almost ready. Then I tried to upload a csv of products and suddenly the site is blank! Nothing shown!

The files were checked via ftp and are untouched. Has anyone seen this before? Also in my admin panel I get a popup saying: “Smarty Debug Console” etc

Al this after uploading a csv (successfully, I see al products at admin area).

Any help?