ValidationError: ManagementForm data is missing or has been tampered with

[Knut Ivar Nesheim]

Hello fellow Django users,

From time to time users of one of my applications has problems with
formsets. More specifically:

...my stuff...
File "/usr/lib/python2.4/site-packages/django/forms/models.py", line
399, in __init__
super(BaseModelFormSet, self).__init__(**defaults)

File "/usr/lib/python2.4/site-packages/django/forms/formsets.py",
line 47, in __init__
self._construct_forms()

File "/usr/lib/python2.4/site-packages/django/forms/formsets.py",
line 91, in _construct_forms
for i in xrange(self.total_form_count()):

File "/usr/lib/python2.4/site-packages/django/forms/formsets.py",
line 70, in total_form_count
return self.management_form.cleaned_data[TOTAL_FORM_COUNT]

File "/usr/lib/python2.4/site-packages/django/forms/formsets.py",
line 57, in _management_form
raise ValidationError('ManagementForm data is missing or has been
tampered with')

ValidationError: [u'ManagementForm data is missing or has been tampered with']

This only happens for Internet Explorer 6, 7 and 8 users. When looking
at the source of the page, all the correct fields are there(even in
the browsers mentioned). When I check request.POST I find all the
fields from the management form(total forms, initial forms and max num
forms). The only difference I can see from the error in the production
environment is that max num forms is missing from request.POST, could
this be causing the error?

Kind regards,
Knut Nesheim

[DrMeers]

I have the same problem -- only intermittently, only IE, can't put my
finger on what is causing it. A couple of times a month I get an
emailed error message coming through. I have not been able to
replicate it on my machine, even using IE and performing the same
operation; very odd.

[Gramware]

Try this for a solution http://stackoverflow.com/questions/2536285/django-formset-management-form-validation-error

[Dane Kennedy]

I'm getting the same thing, except it's 2018 >:/. I'm waiting to hear from users if they're using IE, but do you think there's any chance this is still a problem?