If you used my block updates script below
adb shell mount -o rw,remount -t ext2 /dev/block/mmcblk0p5 /system
adb shell mv /etc/security/otacerts.zip /etc/security/otacerts.zip_DISABLED_OTA_UPDATES


too undo it you would do
adb shell mount -o rw,remount -t ext2 /dev/block/mmcblk0p5 /system
adb shell mv /etc/security/otacerts.zip_DISABLED_OTA_UPDATES /etc/security/otacerts.zip

That would rename the old file back to normal