New release: 1.3.9


Despite the current heat wave pressing down on Germany making development harder than usual, I’m happy to present you OctoPrint 1.3.9. This is a true maintenance release again, consisting of various improvements and fixes. It was made possible only through your continued support of my work 💕.

The most important thing first: If you are still running OctoPrint 1.3.6 when updating to this (or a later) release, you will get a message that the update failed. This is in fact not the case and caused by an issue only in the update mechanism in 1.3.6 that has since been fixed in 1.3.7/1.3.8. Just in case though, if you get this message, simply trigger the update again by clicking on “Check for update now” under Settings > Software Update and clicking the “Update Now” button in the notification again. The release notes also contain some more details on this and there is also an FAQ entry on this.

Also, if you are running OctoPrint behind NGINX as a reverse proxy or have IPv6 support disabled on the system running OctoPrint, please make sure to read the additional heads-ups in the release notes.

With that out of the way now on to some highlights from the release notes:

  • A very annoying race condition causing OctoPrint to get stuck in “Cancelling” or “Pausing” state was identified and fixed. See also this FAQ entry which outlines the workarounds for this issue if you didn’t yet come across them.

  • An observed incompatibility with pip versions 10 and after that caused issues with plugin installation/uninstallation was also identified and fixed (see here for details).

  • Added support for plugins to override GCODE analysis provider and live print time estimation with their own implementations through two new hooks octoprint.filemanager.analysis.factory and octoprint.printer.estimation.factory. Feel free to go nuts with this!

  • Allowed more granular control over components to be upgraded through the software update plugin in its settings dialog. Instead of performing an “all-or-nothing” update, you may now apply each update individually.

  • Added detection for more unsafe firmwares to the bundled Printer Safety Plugin:

    • Anycubic Mega
    • Malyan M200
    • CR-10S
    • all Repetier firmware versions prior to 0.92
    • any firmware that reports the THERMAL_PROTECTION capability as disabled to thermal protection warning (see also MarlinFirmware/Marlin#10465)
  • Added a new bundled plugin “Action Command Prompt support” that allows printer firmware to trigger confirmation/decision dialogs in OctoPrint (e.g. for filament swaps).

  • The bundled web server Tornado was updated to a newer version to work around issues with client IP logging and other things. This also led to the discovery of a heads-up for anyone running OctoPrint behind NGINX - please see the release notes for details on this.

  • As announced with the release of OctoPrint 1.3.6, the legacy plugin bundling flag has now been removed again. Plugin authors, please make sure to check and if necessary fix your plugins if you haven’t done that so far!

  • Of course there were also quite a number of bugs fixed reported for earlier versions, e.g. the logged in user switching to _api if the general API key was used to access the API in the same browser instance, inconsistencies in the port and baud rate lists between connection and settings dialog, a race condition in resend handling in case of missing oks, plus various fixes of typos and grammar in the documentation.

  • … and much more

As always this is only a small excerpt, the full list of changes can of course be found in the release notes.

Also see Further Information and Links below for more information, where to find help and how to roll back.

I want to also thank everyone who contributed to this release, especially @benlye, @dadosch, @dforsi, @ganey,@malnvenshorn, @ntoff, @tedder and @vitormhenrique for their PRs.

And last but not least a huge Thank you! to everyone who reported back on the release candidates this time: arhi, b-morgan, brandstaetter, buchnoun, CapnBry, chatrat12, ChrisHeerschap, christianlupus, chrisWhyTea, Crowlord, ctgreybeard, Cyberwizzard, DrJuJu, ejjenkins, fieldOfView, FormerLurker, four-of-four, Galfinite, gege2b, HFMan, jjlink, jneilliii, JohnOCFII, jwg3, kazibole, larp-welt, McFly99, mod38, ntoff, OutsourcedGuru, paukstelis, pingywon, pscrespo, Rapsey, tech-rat, tedder, thess, Thisismydigitalself, tibmeister.

Further Information

It may take up to 24h for your update notification to pop up, so don’t be alarmed if it doesn’t show up immediately after reading this. You can force the update however via Settings > Software Update > Advanced options > Force check for update.

If you get an error about “no suitable distribution” during update, please read this.

If you have any problems with your OctoPrint installation, please seek support on the community forum.


This is a companion discussion topic for the original entry at


I upgraded with no issues. I'm really excited by the 'Action Command Prompt Support' plugin!


Exactly what does "◦all Repetier firmware versions prior to 0.92" mean. I just checked my printer and it appears to have 0.91.


It means what it says. I talked to Repetier and he told me that he only introduced thermal runaway protection in 0.92, so any older versions don't have it.


So it's not like if I install 1.3.9 that Octopi will stop working because my 0.91 Repetier is on an unsafe software list? I don't like to upgrade something that is working to suddenly end up with all sorts of unwanted 'features' to 'enhance my printing experience'.


It will warn you about your unsafe firmware setup, but it will not refuse to print or anything like that.


Super. And thanks for all your hard work.


Trying it out now... along with New Prusa 3.3.1 Firmware.
I am only about 10 minutes into the print but no issues so far...


Congrats on the release! You are awesome!


i have this issue:

Could not install packages due to an EnvironmentError: [Error 5] Access is denied: 'c:\users\cencio\appdata\local\temp\pip-uninstall-659ojb\octoprint\venv\lib\site-packages\psutil\_psutil_windows.pyd'
Consider using the --user option or check the permissions.



Did you follow these instructions?

Updating your [Windows-based] OctoPrint installation

Due to the nature of Windows it's sadly not possible to have OctoPrint update itself like on other OSes (e.g. a Raspberry Pi running Linux/OctoPi). When you get an update notification, attempting to apply the update from within OctoPrint will fail. You'll have update manually:


great thanks. I used the command:
while the version was Maintenance and the command:


Upgraded from 1.3.8 (OctopPi 0.14) to 1.3.9 without any issues. Thanks for the great work.


OctoPrint 1.3.9 installed

Tester: OutsourcedGuru
Printer: Robo C2
Extruders: 1
Bed: unheated
Workstation: OSX High Sierra 10.13.6, Safari 11.1.2, 13" display on MacBook Air @ 1400 x 900
Version: 1.3.9

  • Everything appears to work as expected by upgrading via the Notification mechanism.
  • Although I have PrintTimeGenius installed, it's currently disabled since it appears to interfere with the Close button on the Settings dialogs.


Octoprint 1.3.9 installed, no problems encountered so far.