Solved Input/output error on LVM Partition

LVM partition Input/output error ? this error was founded when i use tools vgscan . Because my system not using LVM partition, i use tools vgscan and vgchange to access lvm partiion on Compact Flash My development machine.
default on Compact Flash has 2 partition. 1st for boot partition and the 2nd LVM partition. This error will appear the 2nd time i access (using vgscan)
but when i reboot my computer, then start again to access (offcourse use vgscan and vgchange) will not appear. The mistake what i did when access using tools :

vgscan 

and

vgchange -ay

Then mount as ussually partition :

mount /dev/mapper/lvVol-root /mnt

When i've done using it, i just release with :

umount /mnt

And didn't release with vgtools, (this is what should i do after umount):

vgchange -an

So you will not getting this error again :

root@itech maret # vgscan
  Reading all physical volumes.  This may take a while...
  /dev/VolGroup00/lvolroot: read failed after 0 of 4096 at 2621374464: Input/output error
  /dev/VolGroup00/lvolroot: read failed after 0 of 4096 at 2621431808: Input/output error
  /dev/VolGroup00/lvolroot: read failed after 0 of 4096 at 0: Input/output error
  /dev/VolGroup00/lvolroot: read failed after 0 of 4096 at 4096: Input/output error
  /dev/VolGroup00/lvolswap: read failed after 0 of 4096 at 4128768: Input/output error
  /dev/VolGroup00/lvolswap: read failed after 0 of 4096 at 4186112: Input/output error
  /dev/VolGroup00/lvolswap: read failed after 0 of 4096 at 0: Input/output error
  /dev/VolGroup00/lvolswap: read failed after 0 of 4096 at 4096: Input/output error
  /dev/VolGroup00/lvolcf-rw1: read failed after 0 of 4096 at 436142080: Input/output error
  /dev/VolGroup00/lvolcf-rw1: read failed after 0 of 4096 at 436199424: Input/output error
  /dev/VolGroup00/lvolcf-rw1: read failed after 0 of 4096 at 0: Input/output error
  /dev/VolGroup00/lvolcf-rw1: read failed after 0 of 4096 at 4096: Input/output error
  /dev/VolGroup00/lvolcf-rw2: read failed after 0 of 4096 at 440336384: Input/output error
  /dev/VolGroup00/lvolcf-rw2: read failed after 0 of 4096 at 440393728: Input/output error
  /dev/VolGroup00/lvolcf-rw2: read failed after 0 of 4096 at 0: Input/output error
  /dev/VolGroup00/lvolcf-rw2: read failed after 0 of 4096 at 4096: Input/output error
  Found volume group "VolGroup00" using metadata type lvm2

My tips : PLease Read All the Manual first