SUMMARY
Kstars/Ekos seems to have a bug that appears when trying to do remote plate solve from Kstars on Windows 10 connected to the indi server on a Raspberry Pi4.


STEPS TO REPRODUCE
1. Use KStars on Windows 10 to connect to Raspberry Pi4 using an equipment profile with Telescope Simulator, CCD Simulator and Astrometry.
2. Slew the telescope simulator to any star in your favorite constellation
3. Go to Align module in Ekos
4. Click Options...
5. For Astrometry.net check the checkbox with text "Use Sextractor not python" and click OK
6. On the alignment tab choose Astro.net in the bottom and select "Remote" in the drop down menu
7. Select "Slew to Target" in the top and click "Capture & Solve"
8. Observe that the solver fails 1 millisecond after the remote solver was started.


OBSERVED RESULT
With the SExtractor setting enabled the solver always fails 1 millisecond after the remote solver was started.


EXPECTED RESULT
I would expect the plate solve to succeed remotely like it does when the SExtractor setting is disabled and like it does directly on the Pi4 both with the SExtractor setting enabled and disabled.


SOFTWARE/OS VERSIONS
Windows: Windows 10 Home
Linux/KDE Plasma: StellarMate OS v1.5.2
Kstars on Windows: 3.4.2
Kstars on Raspberry Pi4: 3.4.2


ADDITIONAL INFORMATION
After reproducing the issue I can make the plate solve succeed by following these steps.

1. Go to "Options..." again
2. Remove the checkmark from "Use Sextractor not python" and click OK
3. Click "Capture & Solve" again

Then the solver completes in 5 seconds.

I also tried via VNC directly on the StellarMate (Pi4).
Here I have of course selected "Offline" next to Astro.net on the Align Ekos module.
And here it works fine both with and without the Sextractor setting checked.