Error after plugin instalation

I installed a plugin and since then I get an error when I open my site.
That's what I see:

Array
(
[text_items] => 0 item(s) - $0.00
[text_shop] => Shopping now
[text_shop_cart] => My cart
[text_title] => Product added to Cart
[text_thumb] =>
[text_success] => %s added to shopping cart!
[text_items_full] => text_items_full
[text_empty] => Your shopping cart is empty!
[text_cart] => View Cart
[text_checkout] => Checkout
[text_recurring] => Payment Profile
[text_loading] => Loading...
[button_remove] => Remove
[products] => Array
(
)

)

Which OpenCart version you are using?

The plugin you installed via vQmod xml file or you overwrite system files?