USB sticks are commonly used to quickly exchange data between machines without any direct connection. Of course, you can use the handy devices on every macintosh as well as on PCs. Clearly one cannot install Windows applications on Apples OS X or vice verca. The problem is though, that if you not only want to open/read content from the external medium but also write/copy data onto your Mac, the stick must have a compatible file system.
A Mac differs in several areas from a Windows PC. The competing operating systems offer pretty much the same functionality, the OS handling however is completely different. While many USB sticks use the standard Windows file system NTFS, Mac runs on AFS and is also able to work with FAT32.
In order to check out what file system is currently installed on your stick, open Finder, right-click on the USB device and select Informations. The Info window will open and under General there will be a Format entry. If you were, so far, not able to write on the stick the entry will probably state NTFS. Therefor you need to reformat the USB device if you want to have full access to your stick on Mac. Fortunately, OS X comes with the appropriate tool to do so. Before you undertake the following steps, please make sure to backup all files that are on the USB stick. Reformatting the device will inevitably delete everything on it.
- Plug-in your USB device
- Open the Finder and go to your hard drive
- Go to Applications and open Utilities
- Open Disk Utility
- To the left, choose your USB device, not the underlying current partition
- Select the Delete tab to the right
- Choose the new format (I would recommend FAT)
- Assign a name to the new stick format (optional)
- Hit the Delete button to the lower right
The disk utility app will now reformat your USB stick. If you selected FAT as the new format, you will now be able to read/write on both Windows and Mac systems.