How do I fix the flash is not detected?

The following is just a way for computers with the Windows OS

1. Insert the stick into the USB port of the computer. If detected appears in the usual hard drive or in My Computer after a while.
2. If it appears try to right click on the USB drive icon and then left click on format. Choose FAT32 for operating systems beyond Windows 98. Click start and then format.
   
or by way of:

1. Download an application called HDD Low Level Format Tool
http://www.techspot.com/downloads/5265-low-level-format-tool.html
2. Then install as usual
3. Open the application we will look at the screen all the disk drives detected
4. Select the flash to be repaired and then click "continue". Ensure that you have the correct drive not to any
5. Then select LOW-LEVEL-FORM and click Format this device
6. Well, now the flash is ready for use, before we have to format it first

   
May be useful