When you transfer files from iMac to usb you get a symbol that prevents you this action?

If you're encountering a symbol that prevents file transfer from your iMac to a USB drive, it may indicate that the drive is either not formatted correctly or is write-protected. To resolve this, check the USB drive's format in Disk Utility; it should ideally be formatted as exFAT or FAT32 for compatibility with macOS. Additionally, ensure the USB drive isn’t locked or restricted in any way. If the issue persists, try safely ejecting and reconnecting the drive or using a different USB port.