Smart Ways to Speed Up Slow Network File Transfer in Your Mac

Many users reported that the Network File Transfer speeds have considerably slowed down after once they upgraded their Mac to OS X. It turns out some of these reports are correct indeed, as Apple has enabled the Client Signing functionality for file transfers through the SMB Protocol in OS X. This was done to protect files from eavesdroppers. However, the users who were using this channel have reported that it drastically reduced the flow of the data sent over the network between Mac-to-Mac transfers as well as Mac-to-PC transfers.

If you think this issue is due to a very large number of files being transferred, chances are there might be a significant number of duplicates involved. Check for duplicate files of all types on your Mac by unleashing the potential of Clone Files Checker.

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Some users have reported that this happens when users upgraded their Mac to the latest version without installing a clean version.

However, the involvement of other factors that lead to this eventuality cannot be ruled out at this stage. Below you will find a handful of solutions that will help you wrest the slow Network File Transfer issue in Mac.

Turn On SMB Network Sharing

If you are using AFP File Sharing, then there is a chance you can speed-up the network file transfer speed on Mac by enabling SMB sharing over the network. To do so, please follow these steps:

1. Open Menu and select System Preferences.
2. Click the Sharing panel.
3. You will find File Sharing under the Service tab, turn it on.
4. Now select the folder you want to share under the Shared Folders list. You will need to select the whole folder instead of selecting individual files.
5. Now select Options and check Share files and folders using SMB (Windows).
6. Select users to whom you want to provide access to and finally click Done at the end.

Clean Install an Upgrade

If you have upgraded your computer without performing a fresh install of OS X, chances are that file transfer will be much slower than normal speeds. This is an old problem of Apple Mac upgrade and has been reported extensively on the Apple support forum. The solution is to perform a clean install of OS X.

1. Download the copy of OS X.
2. Create a bootable version of Mac OS X.
3. Install the volume on an empty drive.
4. Now follow the onscreen instructions for successful installation.

Try Resetting NVRAM on Macbook

Though NVRAM isn’t associated with File Transfer in any way, yet Mac users have reported that resetting NVRAM has actually improved the transfer speeds over the network.

1. Shutdown your Mac.
2. Press and hold these four keys for 20 seconds
   (a) Option
   (b) Command
   (c) P
   (d) R
3. Your Mac will appear to restart. When you hear the startup sound, you can release them.
4. You might have to adjust any settings and system preferences that might have reset.

The problem is higher latency

If the problem is higher latency on the Mac, then you can force a CIFS connection instead to get better results.

To do so, first disconnect from the file server and then select Go | Connect to Server from the Finder menu bar.

Now type in cifs://server-address (Server address can be the IP or the domain name of the server).

If this doesn’t help out then either your device or the end user’s device has limited bandwidth.

Disabling Client Signing on Client and Server End

Client End

In OS X, Apple has added a new feature through which files being sent over the network are signed by the Apple device that prevents other users from accessing it. This feature slows the file transfer speed because the file is being verified by the client.

To disable it:

Simply go to nsmb.conf file located at /etc folder of Mac and add

Client_signing=no

Server End

If your Mac is hosting the file, then disable it by opening the Terminal and adding these lines:

sudo defaults write /Library/Preferences/SystemConfiguration/com.apple.smb.server SigningRequired -bool FALSE

sudo /usr/libexec/smb-sync-preferences

This link explains it all.

Use iDoctor app

Sometimes, you are just not able to find a successful solution. In that case, run a diagnostic scan by the iDoctor app. You can also get technical support from iDoctor to fix the issue.

Also remember, not to

1. Mess up with the MTU size.
2. Go into the System folder of your Mac.