Yesterday encounter a K2
module error When label modules have set [ in the specified category ] when
But the specified class does not have any item sometimes
For example no items released
Or in the language of the situation This classification is no item when
Error occurs

But worse
When you use some version of the type when
Error message is not reported
But only display error code of
The mistake he shows 0
error 0 ?
The result is mysql query error
Usually occurs in in ()
when this query And the trouble is
If an error occurs in the module
Sometimes you will find it hard to know which one module or component error occurred
Unless you see his error message
So this point is need to pay more attention in this

Conclusion...

When an error is occurring on every page.
You can try to turn off the module to find out where the error in