From the looks of it, this is a ROBLOX error where they might have spelled their function improperly. The reason I believe it is ROBLOX's issue is due to the fact the directory is Model.MainModule, though I could be wrong.
Roblox publishing failed reason maybe was:
-Their service was being false or bugged. This bug was really unique to be seen.
-cURL (Stands for [Client URL](https://www.drupal.org/project/client_url)) Error. Commonly some of the reason is the cURL bugged of goes false.
-The ROBLOX is currently updating, or testing, so it might make the ROBLOX off a while.
-You got an issue on your computer!
~~~**SOME WAYS TO FIX**~~~
Maybe you can try those ways,
1) `Rebooting or restarting` your computer. Somehow the issues from some from the computer that's don't load properly or any issues that the reason has made them failed to publish.
2) `Reinstall` them. I believe somehow that might not be working. But I kept believing it might work for some reason. The best way to reinstall is `Start bar > Control panel > Programs and Features > Select ROBLOX Studio > Reinstall`.
3) `Log out and log in again`, this maybe was not working too, I also believe this will might work in some specific reason.
4) `Reset ROBLOX settings`, some reason that doesn't work maybe it's the ROBLOX settings, the ROBLOX settings are located in `ROBLOX Studio > File > Settings...`,
5) `Disable some script that has too many lines`, some script has too many lines, or a part have too many scripts, that may cause them bug or system false.
Hope I helped and best of luck! Bye!
And if you try out those and not working, then you'll just wait for some days like 3 or 5 days, they will automatically fix or you'll figure out the problem yourself.
~~~**Some problems that same like you**~~~
[Can't publish](https://robloxforum.com/threads/cant-publish.25293/) - Made by SjorsApenWorst - Made on Jul 24, 2018.
~~~**Some same problems picture**~~~
[(Blank name)](https://imgur.com/lTBwe5K/) by SjorsApenWorst - Made on Jul 25, 2018 - Picture from Imgur.
4 comments
Do you have any saved files on your computer?
Yes, a lot.
Approximately 20 or so.
Maybe use Imgur instead of gyazo and some strange picture website to send the picture to us