Software version mismatch (win 10)

Just downloaded and installed from MS store, first time playing and I'm prompted to run a file check, but I don't see the option in the launcher, also trying to test connection It give error code 403

Hmm your posting time looks like it was just as the servers were down. That said, I had the same error, and I needed the following:

  1. Press start button (the Windows start button)
  2. Select "Microsoft Store"
  3. Click the "Get Updates" button at the top-right of the screen (although by click I mean spam: I clicked it about 3 times) a. Phantasy Star Online 2 should begin downloading
  4. Wait for the download to finish
  5. Phantasy Star Online 2 should now be under "Recent activity" instead of having the download bar
  6. Restart computer (unfortunately this is needed because otherwise it won't log in to your ship)
  7. Wait for computer to restart fully
  8. Open Xbox app
  9. Launch Phantasy Star Online 2 from the Xbox app
  10. You should now be able to play normally