Issues with large file transfers (SMB)

[Spider99]

When you say stuck - how long did you wait?
How long after a reboot do you do this transfer?
What else is the nas doing when you do the transfer?
Do you have disk spindown enabled?
What type of disks are you using?

Calculating - i believe is windows waiting on the NAS to confirm it has space available and reserved for the transfer and the files do not already exist etc - i.e. it needs info to proceed

I get it occasionally from my desktop to my 853a but only for a few seconds - usually when i have not accessed the nas for a while so the disks spin down etc

[Spider99]

its not win 10 its the nas building a file list for the directory you are copying to for win 10 to be able to decide how to proceed - flag up file conflicts / not enough space/ etc etc - until it gets that data it "calculates"

If you do this very quickly after the nas boots - its probably still doing its basic startup tasks - even though you can get access via a shared folder/the gui

You have a large volume of data on the nas so the nas needs to cache the directory structure(as lost after reboot) and files in memory and as you have probably 100k's of files it will take some time - i would guess the reason it works the second time is that by then it has the cache fully populated

The fact you do not get this to an external disk or local disk on your desktop is not that relevant as they are connected differently or have significantly less file/folders to load - so you don't see the calculating bit of the dialog although it still happens.