Hello,

I am facing a problem that after i made my website on odoo, my odoo system cannot login anymore.

Here is the log:

2019-04-03 11:12:12,599 7669 ERROR odoo_db odoo.addons.website.models.ir_http: 500 Internal Server Error:

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/odoo/addons/base/models/qweb.py", line 346, in _compiled_fn
    return compiled(self, append, new, options, log)
  File "<template>", line 1, in template_173_286
  File "<template>", line 2, in body_call_content_285
TypeError: object of type 'NoneType' has no len()

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/odoo/addons/base/models/ir_http.py", line 203, in _dispatch
    result = request.dispatch()
  File "/usr/lib/python3/dist-packages/odoo/http.py", line 833, in dispatch
    r = self._call_function(**self.params)
  File "/usr/lib/python3/dist-packages/odoo/http.py", line 344, in _call_function
    return checked_call(self.db, *args, **kwargs)
  File "/usr/lib/python3/dist-packages/odoo/service/model.py", line 97, in wrapper
    return f(dbname, *args, **kwargs)
  File "/usr/lib/python3/dist-packages/odoo/http.py", line 340, in checked_call
    result.flatten()
  File "/usr/lib/python3/dist-packages/odoo/http.py", line 1268, in flatten
    self.response.append(self.render())
  File "/usr/lib/python3/dist-packages/odoo/http.py", line 1261, in render
    return env["ir.ui.view"].render_template(self.template, self.qcontext)
  File "/usr/lib/python3/dist-packages/odoo/addons/base/models/ir_ui_view.py", line 1284, in render_template
    return self.browse(self.get_view_id(template)).render(values, engine)
  File "/usr/lib/python3/dist-packages/odoo/addons/website/models/ir_ui_view.py", line 318, in render
    return super(View, self).render(values, engine=engine, minimal_qcontext=minimal_qcontext)
  File "/usr/lib/python3/dist-packages/odoo/addons/web_editor/models/ir_ui_view.py", line 27, in render
    return super(IrUiView, self).render(values=values, engine=engine, minimal_qcontext=minimal_qcontext)
  File "/usr/lib/python3/dist-packages/odoo/addons/base/models/ir_ui_view.py", line 1293, in render
    return self.env[engine].render(self.id, qcontext)
  File "/usr/lib/python3/dist-packages/odoo/addons/base/models/ir_qweb.py", line 59, in render
    result = super(IrQWeb, self).render(id_or_xml_id, values=values, **context)
  File "/usr/lib/python3/dist-packages/odoo/addons/base/models/qweb.py", line 274, in render
    self.compile(template, options)(self, body.append, values or {})
  File "/usr/lib/python3/dist-packages/odoo/addons/base/models/qweb.py", line 353, in _compiled_fn
    raise QWebException("Error to render compiling AST", e, path, node and etree.tostring(node[0], encoding='unicode'), name)
odoo.addons.base.models.qweb.QWebException: object of type 'NoneType' has no len()
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/odoo/addons/base/models/qweb.py", line 346, in _compiled_fn
    return compiled(self, append, new, options, log)
  File "<template>", line 1, in template_173_286
  File "<template>", line 2, in body_call_content_285
TypeError: object of type 'NoneType' has no len()

Error to render compiling AST
TypeError: object of type 'NoneType' has no len()
Template: 173
Path: /templates/t/t/t
Node: <t t-set="form_small" t-value="True" t-if="len(providers) &gt; 2"/>

However I am new to odoo and i really have no clue on how to fix this. Sure i google this "errors"  on google but really no hope. Would you please kindly help on this how can i start solving this problem?

THanks