Hi
you already did a good job fixing this error. However, you may have forgotten just a few small things.
This happened when you decided to hit the 'reset button'.
You noticed that you have to point out to the correct directory since you store the data on an external hard drive.
Have you changed the setting "datadir" in the bitcoin.conf file with the exact directory?
The error code clearly says that pruning is not possible when -txindex is enabled.
So if you use 'txindex=1' you also need to set prune to 0 to disable it. Make sure that 'prune=0' is set - any other value enables it.
This steps should already fix your problem, try em out, save the options and restart ur node.
If there are still problems, you could check the debug logfile for further errors, which will also be on your external drive directory.