nginx 1.4.2 [error] 2516#12636: CreateFile() (1 reply)

i added the cache configuration in my nginx.conf ,like this :

location ~ .*\.(js|css|ico|jpg|jpeg|png|gif)$
{
expires 7d;
root cache;
proxy_store on;

}
But i coudlen't login my app ,the error log is :
2014/05/07 09:27:13 [error] 2516#12636: *11 CreateFile() "D:/myapp/nginx-1.4.2/cache/myapp/static/msgengine/msgengine.js" failed (3: The system cannot find the path specified), client: 192.168.3.112, server: 0.0.0.0, request: "GET /myapp/static/msgengine/msgengine.js HTTP/1.1", host: "10.1.1.7", referrer: "http://10.1.1.7/myapp/index.action"