Vegetto, download Configmagc and put it on your Xbox. Put the EEPROM.BIN (which I will give you soon) in its data folder in Configmagic. Run CM and unlock HD. Select "Load EEPROM from BIN File". Select "Update EEPROM". Lock HD. Power off Xbox.
Turn modchip off and run Live. You will be unbanned
If the EEPROM, when loaded, says "PAL, Region 4" you must change it to "NTSC, Region 1" (if you have a NTSC Xbox). You can change this config in the edit on the fly option.
I have most of this info in my pinned topic.