If you have updated your odoo completely then you may have to drop the db ,if you have just updated few module you can update these module from terminal using -u module name. It's may solved the issue

This happened after updaying to the nightly build!

Error log

2016-12-11 14:22:56,376 2531 INFO thegeek odoo.addons.base.ir.ir_http: Generating routing map2016-12-11 14:23:00,250 2531 INFO thegeek werkzeug: 127.0.0.1 - - [11/Dec/2016 14:23:00] "GET /web/ HTTP/1.0" 200 -2016-12-11 14:23:00,628 2531 INFO thegeek werkzeug: 127.0.0.1 - - [11/Dec/2016 14:23:00] "GET /web/content/252-54a49f8/web.assets_backend.js HTTP/1.0" 200 -2016-12-11 14:23:00,756 2531 INFO thegeek werkzeug: 127.0.0.1 - - [11/Dec/2016 14:23:00] "GET /web/content/247-54a49f8/web.assets_backend.0.css HTTP/1.0" 200 -2016-12-11 14:23:00,767 2531 INFO thegeek werkzeug: 127.0.0.1 - - [11/Dec/2016 14:23:00] "GET /web/content/248-54a49f8/web.assets_backend.1.css HTTP/1.0" 200 -2016-12-11 14:23:06,284 2531 INFO thegeek werkzeug: 127.0.0.1 - - [11/Dec/2016 14:23:06] "GET /web/webclient/qweb?mods=base_import,base HTTP/1.0" 304 -2016-12-11 14:23:06,610 2531 INFO thegeek werkzeug: 127.0.0.1 - - [11/Dec/2016 14:23:06] "GET /web_editor/static/src/xml/ace.xml HTTP/1.0" 404 -2016-12-11 14:23:06,630 2531 INFO thegeek werkzeug: 127.0.0.1 - - [11/Dec/2016 14:23:06] "POST /web/dataset/call HTTP/1.0" 200 -2016-12-11 14:23:06,995 2531 INFO thegeek werkzeug: 127.0.0.1 - - [11/Dec/2016 14:23:06] "GET /web_editor/static/src/xml/editor.xml HTTP/1.0" 404 -2016-12-11 14:23:07,143 2531 INFO thegeek werkzeug: 127.0.0.1 - - [11/Dec/2016 14:23:07] "GET /web_editor/static/src/xml/snippets.xml HTTP/1.0" 404 -2016-12-11 14:23:07,328 2531 INFO thegeek werkzeug: 127.0.0.1 - - [11/Dec/2016 14:23:07] "POST /web/webclient/translations HTTP/1.0" 200 -2016-12-11 14:23:07,359 2531 INFO thegeek werkzeug: 127.0.0.1 - - [11/Dec/2016 14:23:07] "POST /web/webclient/translations HTTP/1.0" 200 -2016-12-11 14:23:07,459 2531 INFO thegeek werkzeug: 127.0.0.1 - - [11/Dec/2016 14:23:07] "GET /web/webclient/locale/en_US HTTP/1.0" 500 -2016-12-11 14:23:07,473 2531 ERROR thegeek werkzeug: Error on request: Traceback (most recent call last): File "/usr/local/lib/python2.7/dist-packages/werkzeug/serving.py", line 177, in run_wsgi execute(self.server.app) File "/usr/local/lib/python2.7/dist-packages/werkzeug/serving.py", line 165, in execute application_iter = app(environ, start_response) File "/usr/lib/python2.7/dist-packages/odoo/service/server.py", line 246, in app return self.app(e, s) File "/usr/lib/python2.7/dist-packages/odoo/service/wsgi_server.py", line 184, in application return application_unproxied(environ, start_response) File "/usr/lib/python2.7/dist-packages/odoo/service/wsgi_server.py", line 170, in application_unproxied result = handler(environ, start_response) File "/usr/lib/python2.7/dist-packages/odoo/http.py", line 1306, in __call__ return self.dispatch(environ, start_response) File "/usr/lib/python2.7/dist-packages/odoo/http.py", line 1471, in dispatch result = ir_http._dispatch() File "/usr/lib/python2.7/dist-packages/odoo/addons/web_editor/models/ir_http.py", line 21, in _dispatch return super(IrHttp, cls)._dispatch() File "/usr/lib/python2.7/dist-packages/odoo/addons/base/ir/ir_http.py", line 199, in _dispatch return cls._handle_exception(e) File "/usr/lib/python2.7/dist-packages/odoo/addons/base/ir/ir_http.py", line 169, in _handle_exception return request._handle_exception(exception) File "/usr/lib/python2.7/dist-packages/odoo/http.py", line 766, in _handle_exception return super(HttpRequest, self)._handle_exception(exception) File "/usr/lib/python2.7/dist-packages/odoo/addons/base/ir/ir_http.py", line 195, in _dispatch result = request.dispatch() File "/usr/lib/python2.7/dist-packages/odoo/http.py", line 825, in dispatch r = self._call_function(**self.params) File "/usr/lib/python2.7/dist-packages/odoo/http.py", line 331, in _call_function return checked_call(self.db, *args, **kwargs) File "/usr/lib/python2.7/dist-packages/odoo/service/model.py", line 119, in wrapper return f(dbname, *args, **kwargs) File "/usr/lib/python2.7/dist-packages/odoo/http.py", line 324, in checked_call result = self.endpoint(*a, **kw) File "/usr/lib/python2.7/dist-packages/odoo/http.py", line 933, in __call__ return self.method(*args, **kw) File "/usr/lib/python2.7/dist-packages/odoo/http.py", line 504, in response_wrap response = f(*args, **kw) File "/usr/lib/python2.7/dist-packages/odoo/addons/web/controllers/main.py", line 491, in load_locale addons_path = http.addons_manifest['web']['addons_path']KeyError: 'web'`