I also noticed that, there is no problem to load .css and .js from saphhire folder

SS3
Also getting this error, had it twice now once it went away after I took off DEV mode in my _config.php no idea if that was actually the fix but now its back... Then it happened when I uploaded the site to a server, still not fixed, and now it suddenly happened on my local server.... so annoying.

None of the fixes work for me.
1>Not changing the permissions of _combined or assets or .JS files,
2>not deleting the _combinedfiles folder
3> not adding "Requirements::set_combined_files_enabled(false);" to my _config.php
4> not deleting .htaccess rom /assests/
5> not amending the url with ?isDev=1

Any other ideas???

EDIT
So I copy and pasted my a back up from earlier over the top and its works. But now every time I do www.mysite.com/admin?flush=all
I get stuck again with the loading screen and the only way to go back is to past the old back up over it again.....

EDIT
I find this happens if I add any new lines to my _config.php file. Then refresh the admin. If I take a line away and refresh It loads and accesses the CMS...

jQuery is not defined
[Break On This Error] })(jQuery);
jquery...1322164 (line 163)
Error in parsing value for 'list-style-type'. Declaration dropped.
[Break On This Error] }(jQuery));
lib.js...1322164 (line 235)
jQuery is not defined
[Break On This Error] }(jQuery));
lib.js...1322164 (line 235)
jQuery is not defined
[Break On This Error] })( jQuery );
jquery...1322165 (line 351)
jQuery is not defined
[Break On This Error] }(jQuery));
GridFi...1322164 (line 346)
jQuery is not defined
[Break On This Error] jQuery.cookie = function(name, value, options) {
jquery...1322165 (line 56)
jQuery is not defined
[Break On This Error] }(jQuery.query || {}); // Pass in jQuery.query as settings object
jquery...1322165 (line 224)
jQuery is not defined
[Break On This Error] })(jQuery);
jquery...1322165 (line 1009)
jQuery is not defined
[Break On This Error] })(jQuery);
jquery...1322164 (line 73)
jQuery is not defined
[Break On This Error] }(jQuery));
jquery...1322164 (line 77)
jQuery is not defined
[Break On This Error] if (jQuery && jLayout) {
jquery...1322164 (line 9)
jQuery is not a function
[Break On This Error] jQuery(el).bind(event,callback);
histor...1322164 (line 32)
jQuery is not a function
[Break On This Error] jQuery(el).bind(event,callback);
histor...1322164 (line 32)
jQuery is not defined
[Break On This Error] (function () { if(jQuery && jQuery.jstree) { return; }
jquery...1322166 (line 21)
jQuery is not defined
[Break On This Error] $ = jQuery;
chosen...1322164 (line 283)
jQuery is not defined
[Break On This Error] })(jQuery);
jquery...1322164 (line 106)
jQuery is not defined
[Break On This Error] }(jQuery));
jquery...1322164 (line 127)
jQuery is not defined
[Break On This Error] }(jQuery));
TreeDr...1322164 (line 371)
jQuery is not defined
[Break On This Error] }(jQuery));
DateFi...1322164 (line 36)
jQuery is not defined
[Break On This Error] })(jQuery);
HtmlEd...1322164 (line 1273)
jQuery is not defined
[Break On This Error] })(jQuery);
TabSet...1322164 (line 36)
jQuery is not defined
[Break On This Error] }(jQuery));
ssui.c...1322164 (line 187)
jQuery is not defined
[Break On This Error] }(jQuery));
GridFi...1322164 (line 346)
Unexpected token in attribute selector: '!'.
[Break On This Error]
jQuery is not defined
[Break On This Error] jQuery(function($){
jquery...1322165 (line 6)
jQuery is not defined
[Break On This Error] }(jQuery));
LeftAn...1322164 (line 143)
jQuery is not defined
[Break On This Error] }(jQuery));
LeftAn...1322164 (line 477)
jQuery is not defined
[Break On This Error] }(jQuery));
LeftAn...1322164 (line 50)
jQuery is not defined
[Break On This Error] })(jQuery);
LeftAn...1322164 (line 104)
jQuery is not defined
[Break On This Error] }(jQuery));
LeftAn...1322164 (line 236)
jQuery is not defined
[Break On This Error] }(jQuery));
LeftAn...1322164 (line 262)
jQuery is not defined
[Break On This Error] }(jQuery));
LeftAn...1322164 (line 168)
jQuery is not defined
[Break On This Error] }(jQuery));
LeftAn...1322164 (line 326)
jQuery is not defined
[Break On This Error] })(jQuery);
LeftAn...1322164 (line 379)
jQuery is not defined
[Break On This Error] }(jQuery));
LeftAn...1322164 (line 27)
jQuery is not defined
[Break On This Error] })(jQuery);
LeftAn...1322164 (line 17)
jQuery is not defined
[Break On This Error] }(jQuery));
CMSMai...1322163 (line 342)
jQuery is not defined
[Break On This Error] }(jQuery));
CMSMai...1322163 (line 99)
jQuery is not defined
[Break On This Error] })(jQuery);
CMSPag...1322163 (line 159)
jQuery is not defined
[Break On This Error] }(jQuery));
CMSMai...1322163 (line 55)
jQuery is not defined
[Break On This Error] })(jQuery);
Silver...1322163 (line 35)
jQuery is not defined
[Break On This Error] }(jQuery));
SiteTr...1322163 (line 216)
jQuery is not defined
[Break On This Error] jQuery(function($){
jquery...1322165 (line 6)
jQuery is not defined
[Break On This Error] rawLocale = jQuery('body').attr('lang');