loading sketches issue

Good day to the forum,
I am using Arduino uno and the ethernet shield to work the " web server " sketch.
Everytime that I need to upload a modified sketch I have to remove the ethernet shield.
If I do not remove it than the IDE does not communicate with Arduino giving error.

Is this normal ?
Is there any correction ?
Thanks for the assistance
regards,
Ambrogio

Some ethernet shields don't let the usb reset the Arduino, probably due to an incorrect component on the shield.

If the Arduino doesn't reset, the bootloader doesn't start. If the bootloader doesn't start, the code will not upload and you see an error on the IDE status box.

Try pressing the reset button on the ethernet shield during the compile, then release it when you see the "uploading" message on the IDE.

Thanks a lot for the very usefull reply.
It is working well now.
All the best,
Ambrogio