Same problem here.  Any update on this?

I´m having exactly the same problem with several installations after a Module fails to Install.

Any help is appreciated.

I am currently having the same issue.Please can any one help? As commented by @Klacus this installation path. like: /web_view_editor/static/src/css/view_editor.css those exist.

I've reloaded the latest windows version of Odoo 8 and everything worked fine until I rebooted the server about 15 miuntes ago and when I access the login I get the string of errors below. I'm going to start trouble shooting the problem, but if anyone has experienced this issue or has any ideas, we'd be very appreciative.  Thanks guys.

Could not get content for /web/static/lib/cleditor/jquery.cleditor.css defined in bundle 'web.assets_backend'.

Could not get content for /web/static/lib/jquery.textext/jquery.textext.css defined in bundle 'web.assets_backend'.

Could not get content for /web/static/lib/select2/select2.css defined in bundle 'web.assets_backend'.

Could not get content for /web/static/lib/bootstrap/css/bootstrap.css defined in bundle 'web.assets_backend'.

Could not get content for /web/static/lib/jquery.ui.bootstrap/css/custom-theme/jquery-ui-1.9.0.custom.css defined in bundle 'web.assets_backend'.

Could not get content for /web/static/lib/jquery.ui.timepicker/css/jquery-ui-timepicker-addon.css defined in bundle 'web.assets_backend'.

Could not get content for /web/static/lib/jquery.ui.notify/css/ui.notify.css defined in bundle 'web.assets_backend'.

Could not get content for /web/static/src/css/base.css defined in bundle 'web.assets_backend'.

Could not get content for /web/static/src/css/data_export.css defined in bundle 'web.assets_backend'.

Could not get content for /sales_team/static/src/css/sales_team.css defined in bundle 'web.assets_backend'.

Could not get content for /share/static/src/css/share.css defined in bundle 'web.assets_backend'.

Could not get content for /stock/static/src/css/stock.css defined in bundle 'web.assets_backend'.

Could not get content for /web_calendar/static/src/css/web_fullcalendar.css defined in bundle 'web.assets_backend'.

Could not get content for /web_calendar/static/lib/fullcalendar/css/fullcalendar.css defined in bundle 'web.assets_backend'.

Could not get content for /web_diagram/static/src/css/base_diagram.css defined in bundle 'web.assets_backend'.

Could not get content for /web_gantt/static/src/css/gantt.css defined in bundle 'web.assets_backend'.

Could not get content for /web_gantt/static/lib/dhtmlxGantt/codebase/dhtmlxgantt.css defined in bundle 'web.assets_backend'.

Could not get content for /web_graph/static/src/css/graph.css defined in bundle 'web.assets_backend'.

Could not get content for /web_graph/static/src/css/nv.d3.css defined in bundle 'web.assets_backend'.

Could not get content for /web_kanban/static/src/css/kanban.css defined in bundle 'web.assets_backend'.

Could not get content for /web_tests/static/src/css/web_tests.css defined in bundle 'web.assets_backend'.

Could not get content for /web_view_editor/static/src/css/view_editor.css defined in bundle 'web.assets_backend'.

Hi.

For first look, when you start the server some path, or system varaible is wrong, or missing, that's why didn't found the items. Do you check the wanted items in your installation path. like: /web_view_editor/static/src/css/view_editor.css this file is exist?