Error Using django-tables2 - Expected table or queryset, not 'str'

Had the same problem. I forgot to add SingleTableMixin in the parameters of the view class

I encountered that problem, too. The first thing you should do is to check your updates:

sudo pip install django-tables2 --upgrade
sudo pip install django-tables2-reports --upgrade

Upgrades didn't fix my problem either.
If you have already upgraded version of these. You should check your implementation. If you are using Class Based View and you probably implemented the view,template,table. You probably forget the urls:

/* I give the example with respect to other post*/
urls.py  /*Same dic with table.py,models..etc*/

from .views import SomeTableView   
urlpatterns = patterns('',
                   url(r"^$", SomeTableView.as_view(), name="index"),

                   
                   )

If it is not index of your website you have to probably change the r"^$" and name="index"

Well I think your problem isn't with the version of django-tables2. Here I think when you are passing a variable from view to template, you are passing a string instead of a queryset/table class object. For working example:

Table class:

class SomeTable(tables.Table):

    class Meta:
        model= SomeModel
        attrs = {"class": "paleblue"}

View Class:

class SomeTableView(SingleTableView):
    model = SomeModel
    template_name = 'test.html'
    table_class = SomeTable

Template:

 {% load render_table from django_tables2 %}
 {% render_table table %}   <!-- Here I am passing table class -->

Or you can directly send a queryset to render the table like:

class SomeView(TemplateView):
     def get(self, request, *args, **kwargs):
         data = SomeModel.objects.all()
         context = self.get_context_data(**kwargs)
         context['table'] = data
         return self.render_to_response(context)

and render it like this:

{% load render_table from django_tables2 %}
{% render_table table %} <!-- Here I am passing queryset -->