The item "foldername" could not be moved because "USB-HDD" cannot be modified

The item "foldername" could not be moved because "USB-HDD" cannot be modified error normally happen on Mac when transferring/copying files to an USB or hard Disk because your USB or Hard Disk is formated for Windows only, Mac will be able to read only, not modifying 


Solution:

1. Back up all your data then Format your USB or Hard Disk into FAT 32 in Windows, in this way you can use your device for both Windows and Mac. On windows Machine, Click right your USB or Hard Disk then click format and choose FAT 32 then format it.
2. If you plan to use your  USB or Hard Disk only for Mac then you can format it on Mac by using Disk Utility. Click Spotlight on top right corner of your Mack Desktop and search for Disk Utility then follow the instruction to format it.