Transferring large folders of flac files

Hi folks,
I have about 1.8 TB of music stored in flac files, and the main copy is on an external hard drive. I want to make copies onto other external drives, as well as reload my MyCloud NAS. W10 file transfer always seems to time out, or stop for no apparent reason.

Is there a folder transfer product which would handle the transfer accurately without stopping?

Thanks for your attention.

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OP that is 1.8 TB of file (s). It is usually the file allocation table used and the piece of software used to prepare the drive. You have plenty of space, but the number of files has exceeded the (FAT, NTFS or what ever is use) ability to TRACK the number of files correctly..

I suggest you break up the number of files to copy in 1/4 blocks. Break up the large drives into 1 TB or so per partitions. Use 2 or 3 quality drives. I don't like to go over 75 % of the drivecap or partitions over a TB.. ALL drives I use are split in at least 2 parts, when set up for BACKUP. A boot drive is different, a storage drive is different, a backup drive is different. Usually different they are set up different.

A Boot drive I try to use SSD, a storage drive use redundant drives and back ups, may very.. HDs, Tapes, A LOT of CD, Cloud, RtR, Vinyl, how else do they store STUFF... :-)

It is just good practice.. I think if you break up the file NUMBER being copied at one time, That will make a big difference..

Another way is to BIT copy the drive Clone it.. a couple of times..
Look as SyncBack Pro.
I use it for my photo collection.
It has a wide range of copying protocols.
Good Morning, cmjones:

Total Commander should work and it's free for personal use.
I ended up using Teracopy, a freeware copy utility. A bit slow, but it reliably handled a 1.4 TB Folder. Thanks for your recommendations.

I was just going to recommend Terracopy!  The checksum feature is key.