problems with arduino ethernet

someone knows why the arduino ethernet works fine when connected the USB2SERIAL but when USB2SERIAL disconnect the equipment is unserviceable and crashes.

thanks

someone knows why the arduino ethernet works fine when connected the USB2SERIAL but when USB2SERIAL disconnect the equipment is unserviceable and crashes.

It's likely to be a power-supply issue. How are you powering the Arduino and ethernet shield when not using USB?

How are you powering the Arduino and ethernet shield when not using USB?

I'm not using the ethernet shield, I am using the arduino ethernet and powering it with a transformer 9v dc , I am not understand where is the error but apparently arduino is not a solution

powering it with a transformer 9v dc

Regulated or unregulated? Capable of providing how much current?

the equipment is unserviceable and crashes.

A description of the actual symptoms would be more useful. Does it work for a while, then quit responding?