OS6.6.1 - Admin Page Not Responding

hi, i have readynas 102, was working fine until last update 6.6.1.i get this error when try to check new updates

Operation timeout. Communication error. VERIFY CONNECTION to internet or the DNS setting.

Also I cannot see services in page in system / setting whan i can enter to web page

i didn't do any change in may nas or network, the nas is connecting to our server internal lan "not cloud".
i tried to reinstall os 6.6.1 but nothing happens
i tried to change lan from dhcp to static but nothing happens

i can access all my files ,but i cant access administrator web page.

I used RAIDar no fault detected.

i dont know what to do "reset is not acceptable in my case " , 

any help

thanks in advance