Cannot chose Octoprint  

RE:

I observed this also. It seems you have to create a fresh physical printer. After that it works again as before.
You have to create a new custom profile (physical printer) with your OctoPrint settings from the default preset system profile for you printer.
There you can select "OctoPrint" as type, fill in your LAN/WiFi IP and the API Key and save the profile as a new physical printer. When you click on "Test" you will get "Connection to OctoPrint works correctly."
If you save your 3mf file and open it again, the settings for OctoPrint will still be there, like in my screenshot.
If you just use one of the preset system profiles for your printer and only change the IP/API key there, then save your 3mf file (but create no custom printer profile/physical printer for it) and open it again, the type will have reverted to "PrusaConnect". I guess something was overwritten by the last configuration profile update.

RE: Cannot chose Octoprint

Thank you for the answer and confirmation that I'm not alone.

Trying to do what you suggested I narrowed the issue down to one system preset.

I have the MINI, and the slicer provides me two system presets: 

• Original Prusa MINI & MINI+
• Original Prusa MINI & MINI+ Input Shaper

An attempt to create a physical printer from the latter succeeds. But everytime I chose the first one (doesn't matter either I create it from scratch or startfrom the IS to change the preset afterwards, it behave as described in OP.

What I found, is that the first preset provides limited number of host types (at least PrusaLink is missing). See screenshots

RE: Cannot chose Octoprint

Could it be that the first profile without the "IS" is an old profile from before the latest profile updates? In that case you could try to delete the printer profile and add it again via the Configuration Wizard. Perhaps it will work the same as the other one then?

RE: Cannot chose Octoprint

Both profiles are so-called 'system' ones. I believe they come with the slicer installation. There is no option to remove them.

Also, I have a feeling the system profiles are being updated from time to time. My guess is, that something has gone wrong with v2.8. 

Luckily it still prints via OctoPrint, even if it says it's PrusaConnect.

RE:

No, but you can create a copy with your adjustments as a "physical printer". That one should have the Host Type "OctoPrint" permanently.
Where it says in your screenshot "Type here the name of your printer device" you should input a name for your printer. Then you'll have a "physical printer" with your changes.

RE: Cannot chose Octoprint

No sure I understand. 

The issue I'm describing appears just when I create a physical printer (or edit an existing one), selecting non-IS system preset to be linked with it.

Steps to reproduce:

1. Select non-IS system profile

2. Select add physical printer

3. Select OctoPrint (see, URL is not being changed)

4. enter the OctoPrint address and its application key, and press Test. You can see it reports connectivity to PrusaConnect. Further behavior described in OP

RE: Cannot chose Octoprint

If you do not enter a value in the field "Descriptive name for the printer" your changes will not be saved. Instead the system profile will be used, which cannot be overwritten. Just try to enter an name in that field. In all your screenshots you have not done that, so the changes will not be saved in a custom profile but the settings will revert to the system profile. I hope you understand what I mean.

RE:

If I don’t enter the name here, the physical printer cannot be saved. Note I’m creating new physical printer,  not a profile.

So, yes. I’m entering the name “OctoPrint”. The Slicer then creates the final name consisting of the entered name and profile name the physical printer is based on.

But for performing the test, it’s not needed.

RE: Cannot chose Octoprint

Exactly, and then the setting for "Host type" will be permanently saved in that "physical printer" when you use it to print something. At least that is how it worked for me.

RE: Cannot chose Octoprint

it works like you say only for physical printer created based on IS system profile.

Once the physical printer is created based on non-IS system profile, all issues described in the posts above occur, incl. replacing OctoPrint selection with Prusa Connect

RE: Cannot chose Octoprint

The reason could be that the only official profile for the Mini now is the one with IS. I looked in the Configuration Wizard (I have no Mini) and there is only one type for the Mini and that is the one with IS.

RE:

Then it could be a bug of missing non-IS profile. The non-IS profile is indispensable in some scenarios. Moreover, it contains presets described in the documentation which are lacking from IS profile. I couldn't imagine a lack of non-IS profile.

RE: Cannot chose Octoprint

Perhaps you could revert to an earlier Version of PrusaSlicer which still had this profile?

RE:

OK, I de-installed the slicer to install it from scratch and see what it will look like.

So indeed, during installation, when selecting an owned printer, the MINI is offered with IS only. To get NON-IS profiles, there is a section at the bottom of the list called Legacy. And again, those legacy profile has a bug discussed in this thread.

Quite a pity that Prusa is abandoning quality profiles (NON-IS)

I didn't find an option to simply disable IS. It seems it can be done modifying Gcode only. Still not sure I will get the same quality as I experience with NON-IS profiles.

RE: Cannot chose Octoprint

I meant revert to an older version of PrusaSlicer, like 2.7 something something. I think that version still had the non-IS profile for the Mini.

RE:

Yeah... but it doesn't change anything.

I can print through OctoPrint using non-is profile. It just says it's PrusaConect 😉 Whatever...

Downgrading the Slicer might work (until it has the same issue - I did not print without IS for a long time). But it's a temporary solution, considering Prusa has moved non-is profiles to the legacy section. Thus it's expected they will not support them/fix them etc anymore.

RE: Cannot chose Octoprint

BTW I found the same issue (although reported for MK4) raised yesterday by someone else in GitHub : https://github.com/prusa3d/PrusaSlicer/issues/13286

RE: Cannot chose Octoprint

Yes, I just saw that the non-IS profile for the MK4 has disappeared from the Configuration Wizard as well. The physical MK4 printer without IS now has the same behavior as your Mini. I hope this will be addressed in the next configuration update. Because I like to use the non-IS profiles as well for some models and some filaments like TPU print better without IS or not at all with IS.
We'll see what will happen the next week. I still can revert to a backup of my configuration from before that last update ...

RE: Cannot chose Octoprint

Thank you for your assistance.