Easily Partition an External Drive in Windows 10

 Let's get quickly into the topic! 

1. Open the Windows search box, type “diskmgmt.msc,” and hit enter. The Windows Search Box is the magnifying button icon in the bottom-left corner of your screen.
2. Right-click on your external hard drive and select Shrink Volume. If this option is not available to you, reformat the drive to NTFS and try again.
3. Enter an amount of space that you want to shrink your volume by. The remaining space will be displayed in megabytes.
4. Then click Shrink. This will split the hard drive, with one part becoming unallocated space.  
5. Right-click the unallocated space on your drive and select New Simple Volume.
6. Click Next.
7. Then indicate how big you want the partition to be. If you want to use the rest of the space, enter the maximum disk space indicated above it. Then click Next.  
8. Next, choose what drive letter you want to use. Letters that have already been assigned to other drives will not be on this list, so don’t worry if there are missing letters. Just choose among the drive letters still available.
9. Go to File System and choose a format. Windows will choose NTFS for you because that’s Microsoft’s native filing system. But if you want the external hard drive to also work on a Mac, you should choose exFAT, which is an upgraded version of FAT32.

   Note: The exFAT file system only works on Mac 10.6.5 or later, and Windows XP SP3 or later.

10. Check the Quick Format box, and click Next. 
11. Finally, click Finish. If a pop-up appears telling you to format the disk, click Format Disk. After that, the newly formatted disk will open automatically. 

Partitioning your external hard drive will enable you to perform tasks in one section without affecting the rest of the drive.