Since I got my M1 MacMini in 2020, I have been dealing with an issue where randomly I cannot make big transfers to any of my Unraid NAS's. MacOS and Samba (SMB) just have a history of being shit, and with Unraid ditching AFP support with v7, I was hurting. I have just been dealing with this problem for 5 years.

My issue was always trying to copy anywhere from 30-200gb of video from my MacMini to my Unraid server for either transcoding or archiving. This always resulted in a few different finder errors

• This operation cannot be completed, file is in use.

• This operation cannot be completed (code 100060 error)

This pissed me off be cause these Unraid servers had 10gbe networking and SSD cache pool. On a wim, I decided to research this issue again, and I found two videos that ultimately fixed all finder errors for me. I don't know which of these changes actually solved my issue, but I don't care. I just care that it works. The fixed below involve running a quick command in Terminal, and then adding some custom properties to your SMB settings on the Unraid server.

First, open Terminal on your Mac and enter the following command.

defaults write com.apple.desktopservices DSDontWriteNetworkStores true

Now we need to make these changes on your Unraid server. As a quick overview, here is the process to make these changes:

1. Unmount any of the network shares on MacOS that point to this Unraid server.

2. Stop the Unraid array.

3. Make the changes to SMB settings within Unraid settings

4. Start the array

5. Re-mount any shares on macOS side

Go into SMB settings>SMB Extras>Samba Extra Configuration, and paste the following (but make sure to put the IP address of your unraid server on line 3):

veto files = /._*/.DS_Store/.Trashes/.TemporaryItems/
delete veto files = yes
interfaces = x.x.x.x;capability=RSS,speed=10000000000 
aio read size = 1
aio write size = 1
strict locking = No
use sendfile = No
server multi channel support = Yes
readdir_attr:aapl_rsize = no
readdir_attr:aapl_finder_info = no
readdir_attr:aapl_max_access = no
fruit:posix_rename = yes
fruit:metadata = stream

After making these changes, I made four big transfers ranging from 50gb to 120gb, and they all worked perfectly. I hope you experience the same.

All credit for this goes to these two gentlemen and their videos: North3rdMedia & Geekhead. I just took the collective information I gained from these two videos and put them together. Cheers to both these dudes.