[hide-thanks]open command prompt enter the following:
adb shell
mount -o remount,rw -t yaffs2 /dev/block/mtdblock4 /system
cd /system/etc/security
mv otacerts.zip otacerts.zip.bak

or use root explorer and go to system>etc>security and rename the otacerts.zip to otacerts.zip.bak

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