Is there a max file size for copying to My Cloud?

I’ve tried to copy my photo library file up to my cloud mirror server several times. Each time it fails at 42.92GB (File is 48GB). The error is something like ‘failure to read/write bytes…’. I think it lists error code -36.
I’ve tried using afp and nfs to connect to the server and copy. Same behavior. I can run it again if I need to get the full error string.
Any help, or pointers, would be appreciated.

There’s no hard limit, but larger files are more susceptible to failed transfers due to network errors. This can happen on any NAS.

I understand that - but it failed at the exact same point 3 times now,
using different transfer protocols.

I have inquired and got no good answers yet. I have tried to share 150 pictures of the exhibits in the Malaysian National Museum but it would balk on any after about 25. Anyone running into a fixed max, please include me in the receivers list.