SoftwaresEdge

Appreciate your attention. I will try to reproduce it on my end again on a secondary PC. I will check back and update on how that goes. I see there is an update out recently(3.5.17). Any expectation that it will affect things for this issue? I will assume no since you have not been able to reproduce but wanted to ask just incase.

I had a similar issue and was able to find a work around with a little help from @glennemay's comment above related to setup as a local printer. Version 4.7.1 Issue: When using multiple printers each with an Octoprint instance attached, I was unable to get Cura to properly target the OctoPrint instance related to the selected printer instance. It would always select the same connection config. Not sure but I think it was always the last one in the list. It maybe the last one selected/configured. Issue Details and findings: I have 4 printers in this use case. No matter which one I selected when I would use the "Print with OctoPrint" button it would always go to the same OctoPrint instance. This was working fine for months with just 2 printers (with unique OctoPrint connections) until I decided to add the 3rd and 4th printer into the config and then align a printer profile to an OctoPrint connection config. I tried to get it aligned multiple times, I deleted all the OctoPrint configs ad even the printer configs. Nothing seemed to correct the behavior. I then looked at the config file and could see it was not much different than it was when it was working(looked at a back up) I did a little hunting and looked at the code for the add in. Did not look too deep and did not really grok it given the time spent. Did a little more searching... After reading the above details from @glennemay, his reference to "local printer" made me recall that just a few hours previous to adding the new printers, I had disabled the USB printing feature because it kept sending serial commands on start up to an other project I had connected to the same system causing that project to glitch at receipt of the commands. Putting this together, I re-enabled the USB printing feature and then reassigned each of the printers with an OctoPrint connection config and this corrected the issue. All is working as one would expect. Although, I am now back to the annoying state where my other project gets commands on Cura start up and Cura also owns the serial port while open which means I cant leave Cura open while working on that other project. There must be some reference to the USB printing feature maybe because of the roots of the OctoPrint plug in. If I recall it was based on something that would allow extension of the local serial over the network. Not sure but that would make sense in why these 2 parts of the system would have some interaction issues. So basically from what I found, if you want to have multiple printers all with unique OctoPrint connections in a usable way, you must have the USB Printing feature enabled. Note that this seemed to only be an issue after adding a new OctoPrint connection to the settings once I disabled the USB printing feature. Hoping this helps someone else work this out faster than I did. Also maybe someone can look at the interaction and some how remove the dependency.