Part of a flash drive not detected on Mac but not on Win 7 computer

[manyelski]

I have the awkward issue with a flash drive - it is divided into different clusters and I do not see the main one (3 GB) on the windows computers only the Mgel one as a CD drive and the 200 MB one. How could I make all into one, and see them on both Mac and Win? I apply screenshot.

 

[hwojtek]

Click "View" button on the top left to display the physical storage devices (now your Disk Utility displays logical volumes only). Once you see the physical device, select it and click "Partition" button.

 

[manyelski]

Partition is greyed out on all of them even after doing all this

 

[hwojtek]

You need to select the physical device (the hardware flash drive) and not any of the existing partitions on this flash drive, because you want to re-partition the flash drive.

How about selecting the flash drive (not the partitions) and "Erase"?