Transmit Disk has been discontinued as of Transmit 5.6.0

It’s true. Transmit Disk has been discontinued and will no longer be included with Transmit 5 as of version 5.6.0.

There are a number of reasons for this, the biggest being App Notarization in macOS 10.15 (Catalina). 10.15 requires all apps to be notarized, and Transmit Disk isn’t in a place where we could easily make this happen without fully rewriting it.

As macOS is increasing security more and more every year, this makes it very difficult for the current version of Transmit Disk to continue to work properly on modern versions of macOS. Keeping the older version of Transmit Disk up to date with modern macOS standards has been mostly an exercise in futility: We feel our efforts are better suited toward creating a future-proof version of Transmit Disk that fits well into modern macOS ecosystems.

How to download a previous version

If Transmit Disk is crucial to your workflow, we recommend rolling back to version 5.2.4. This will allow you to continue using Transmit Disk if you’re using macOS 10.14.6 or earlier.

Please note: We cannot guarantee Transmit Disk will work correctly on macOS 10.15 (Catalina). If Transmit Disk is crucial to your workflow, we recommend using caution if you plan on upgrading to Catalina.

The Future

We understand that Transmit Disk is very important to some people. The downside here is that we don’t have an immediate solution for users who rely on Transmit Disk other than downloading a previous version as noted above. We hope to revisit Transmit Disk in the future. Apple has some really interesting new technology coming to Finder, and we hope to take advantage of this in the future when the time is right. Unfortunately, this means we don’t have a proper ETA, but we’ll be sure to make an announcement when we’ve got more to share. (More info below)

FAQs and Troubleshooting

Is Transmit Disk supported in High Sierra (10.13)?

You’ll need to upgrade to Transmit 5.0.4 to mount supported servers in macOS High Sierra. More Info

I’m a Transmit 4 user. What’s The State of Transmit Disk with Transmit 5?

Short answer: Transmit Disk behaves exactly like it did with Transmit 4 when used alongside Transmit 5, but does not include any of the new cloud providers or speed enhancements delivered in Transmit 5.

Transmit Disk supported Server types

  • Amazon S3 (Regions requiring V3 auth and earlier)
  • FTP
  • FTP with Implicit SSL
  • FTP with TLS/SSL
  • SFTP
  • WebDAV

Troubleshooting Transmit Disk

If you’re unable to connect to a Server via Transmit Disk the first recommended troubleshooting step is to perform a regular connection through the Transmit app.

If the problem persists after confirming that you are able to connect through the Transmit app, please check if the Server configuration is listed under either of the unsupported server or unsupported configuration sections below.

Unsupported configurations

  • Amazon S3 - Files larger than 5GB in size
  • Amazon S3 - Regions that require V4 auth support or newer: (Frankfurt, London, Montreal, Mumbai, Ohio, Seoul, etc.)
  • Servers that are not included in known_hosts or that have had their host key change since the last connection
  • Servers without a saved password (Ask on connection)
  • Servers that use SSH keys that are stored in Transmit and/or Panic Sync. If you’d like to use an SSH key with Transmit Disk, you’ll need to store it in your config file. Note: If your SSH key is stored in your config file, be sure to remove the key from Transmit itself.

Unsupported Servers

  • Amazon Drive
  • Amazon S3 with IAM Role
  • Backblaze B2
  • Box
  • DreamObjects
  • Dropbox
  • Google Drive
  • Microsoft Azure
  • Microsoft OneDrive
  • Microsoft OneDrive for Business
  • Rackspace CloudFiles

Technical details and the future of Transmit Disk

Transmit Disk is built on a macOS technology called Kernel Extensions to run and integrate with the Finder. Kernel extensions are designed to add functionality to macOS from the lowest, most privileged levels.

In recent years Apple has started to restrict kernel extensions for increased user privacy and system stability. As of macOS 10.10 Yosemite, kernel extensions must be whitelisted and signed by a special certificate from Apple which is not automatically available to all developers. In macOS 10.13 High Sierra, each kernel extension must also be directly whitelisted by the user from within System Preferences. There have been rumors that post-High Sierra, Apple might restrict the availability of kernel extensions even further.

Additionally, the way the Transmit Disk kernel extension works with Finder is highly synchronous (meaning responses from connected servers need to be fast). The newer cloud-based protocols in Transmit 5 are based on web technologies such as REST and are, by nature, more high-latency and asynchronous than a protocol such as SFTP. This means that integrating these protocols into Transmit Disk’s current architecture is more difficult and prone to errors. From within a kernel extension, running at the lowest layer of the system, an error can sometimes completely take down macOS (the so called black screen of death) requiring a system restart.

After speaking to Apple about all of this, they offered several recommendations for transitioning Transmit Disk to a different architecture that would allow it to integrate better into Finder and the system. While these leads are promising, it does mean a fundamental rewrite of Transmit Disk itself would be required.

Due to this, we did not schedule development of a completely new Transmit Disk alongside our development of Transmit 5. Instead, we opted to make sure the current Transmit Disk worked well alongside Transmit 5. We understand many users love Transmit Disk and would like to have its features available to all of the new cloud providers in the future. As such, we are investigating a new Transmit Disk architecture that would allow all of the wonderful speed and protocol improvements of Transmit 5 to be accessible directly from your desktop. It might just take some time.

This article was last updated on May 16, 2022