After making a Bootable USB drive for installing Operating Systems like Ubuntu via Pen drive using softwares like PowerISO , when you format your pen drive using Windows or Ubuntu it will show about only 2 MB of memory in a 4 GB pen drive .
Follow the steps to format the pen drive properly and restore it back to its original condition.
Step 1: Formating Pen Drive Via DiskPart [ Windows]
Connect the pen drive which needs to be formatted to a system running Windows Operating System.
STEP 1 : open Run using the key combination ( Win key + R ).
STEP 2 : type cmd .To open Command Prompt.
STEP 3 : type diskpart . Run the Pop-up window that appears .
. This opens DiskPart.
STEP 4 : type list disk .
. This will list all the memory storage devices connected to the PC.
STEP 5 : type select disk 1 .
. Usually disk 1 if no other storage devices are connected .
. The number specifies the drive to be formatted.
. drive 0 will be your internal hard disk. Identify and select your disk correctly.
STEP 6 : type clean. This wipes data off your pen drive.
STEP 7 : type create partition primary . This will format the pen drive as FAT.
STEP 8 : now go to My Computer or This PC (as it is listed nowadays) .
Format the pen drive by Right clicking on it and selecting Format option.
This will restore back your pen drive to its usual condition.