I have a SE K810i.
I tried to install the new firmware through the usb cable in SE tools .
after that error message appears on startup Contact Network Opretor.

i asked to a technician he told me that the phone is not permenent unlocked,
(i used in other country network)
and it can't be unlock permenently every time i try to upgrade or flash my phone it will blocked like that
is it true?

Does the message say anything bout "Customization"?

If it does, you just need to upload a custpack. (Link "HB1-06 Custpacks" in my signature)

You can do patch unlock as long as your phone is CID52.

when u unlock it with patch, the phone will lock again when u flash it,but its easy to unlock it again

Yup, you can unlock again by patch.

ok then can i unlock it with my usb cable and setools softwares?
or i need other hardware to do it?
can't do the permenent unlock?

u can,just go and read the tutorials,permanent unlock costs

Er

You can do a temporary unlock which takes effect until your next flash. This is done by a patch unlock using Simox. There are guides lying around, check the Tutorials & Guides Section or search.

Permanent unlock can be done by companies and also if you buy the superexpensive hardware. Costs though.