I used following command to make new partition in my 32 gb Samsung SD card.
sudo fdisk /dev/sdb
Then pressed letter o to create a new empty DOS partition table. But it came up with following warning.
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
When I ignored the warning and tried to complete partition by writing new table to disk by pressing w, it showed following warning and refused to make new tables.
WARNING: Re-reading the partition table failed with error 16: Device or resource busy. The kernel still uses the old table. The new table will be used at the next reboot or after you run partprobe(8) or kpartx(8) Syncing disks.
How do I solve this problem? Please help.