Format an IOS Flash

router1#
dir%Error opening disk0:/ (Invalid DOS media or no media in slot)
router1#show disk0:
Unformatted Partition, please format it.

router1#format disk0:
Format operation may take a while. Continue? [confirm]
Format operation will destroy all data in "disk0:". Continue? [confirm]
Primary Partition created...Size 64 MB
Drive communication & 1st Sector Write OK...
Writing Monlib sectors....
Monlib write complete
Format: All system sectors written. OK...
Format: Total sectors in formatted partition: 131040
Format: Total bytes in formatted partition: 67092480Format: Operation completed successfully.
Format of disk0: complete
router1#