I've looked at several threads on different forums and none quite solve the issue I am having. I have a rooted Desire (which took a while and wasn't successful following any guide, but I got it) using unrEVOked 3.21 and am trying to use AdFree on Froyo 2.2 but I am told that the hosts file I need to block ads cannot be written to /system while Android is running. I did some searching but, alas, no luck on an answer. I also got Root Explorer off the market (which cannot simply copy the hosts file into /system/etc/ as it does not have access whilst Android is running) and I think the command prompt I need is the pc cmd prompt when the device is plugged into USB. I got the Android SDK with adb and made progress, but still stumped. I connect the Desire to the PC and with the Desire in recovery mode with ClockworkMod I run adb with: Code (Text): adb shell # mount /system # exit adb push hosts /system/etc adb reboot Following the example from here but it's a different device and dunno what to put for the first argument in '# mount /dev/block/mtdblock4 /system'. Any help at all would be much appreciated.