[0.14.21] Between launches, everything has broken

[boltzman111]

Game was launching, saving, and running fine up until yesterday.

Steps:
-I saved my game as per usual and shut down PC for the night.
-Upon launching the game the next morning, the game opened in windowed mode, and loaded all the mods I had previously used but had disabled for my current play.
-Once loaded, the error message: "Data error, Failed to load local achievement data. Local achievements might be lost." popped up over the main menu
-Clicked OK to close the error message
-Chose Play > Load Game
-When my current manual save is selected, popup says: "Notice, Opening zip C:/.../AppData/Roaming/Factorio/save/KoS.zip failed: Result too large"
-Clicked OK to close the Notice message
-I looked in appdata, and my KoS.zip file is only 26MB, definitely not too large. Searching forums seems to say that this error indicates a corrupted save file.
-Luckily I have the autosaves to revert to, which I have done so without issue.
-However upon launching the auto saves my hotkeys and settings in general are gone. It seems like the game is resetting to default values every time I launch
-Each launch is in windowed mode now, it was loading all mods (but I've since removed them), erasing my customized hotkeys, shows Tips and tricks at the start of every load even though I've specified not to show them again
-There was also suddenly a strange issue with my blue print book, but now I can't reproduce it so I won't mention it.

System Specs:
Intel i7 3770k
EVGA GTX1070
16GB DDR3 RAM
Windows 10 64 bit
3 monitors (1920x1080 or 2560x1440)

[Rseding91]

"result too large" means the save file is corrupt.

The fact that both your achievement data and the map corrupt at the same time indicates there's something wrong on your end - perhaps bad RAM, hard drive, or power loss when trying to save.

[boltzman111]

That could explain the save and achievement data, but what about the launch configuration issues? I've uninstalled and reinstalled. Same windowed mode and loss of customized settings every launch.

[daniel34]

That could explain the save and achievement data, but what about the launch configuration issues? I've uninstalled and reinstalled. Same windowed mode and loss of customized settings every launch.

This is probably a permissions issue where Factorio can't write to the config files. Backup your save files and mods somewhere, then delete the complete %appdata%\Factorio directory. Factorio will create new files the next time it launches, and hopefully they will be writeable in the future.
You could maybe also get away with only deleting the config folder instead of the whole Factorio folder.

[boltzman111]

That could explain the save and achievement data, but what about the launch configuration issues? I've uninstalled and reinstalled. Same windowed mode and loss of customized settings every launch.

This is probably a permissions issue where Factorio can't write to the config files. Backup your save files and mods somewhere, then delete the complete %appdata%\Factorio directory. Factorio will create new files the next time it launches, and hopefully they will be writeable in the future.
You could maybe also get away with only deleting the config folder instead of the whole Factorio folder.

Bingo, that fixed it! Nice one.

[navry]

Just had the same problem as posted originally, daniel34´s suggestion helped me.
Deleting only the Config folder did the job. Any idea how this suddenly happened or how to prevent it?

[posila]

Any idea how this suddenly happened or how to prevent it?

I am going to blame it on turning off PC before Steam finished syncing your saves to Cloud.
I'd suggest you to turn off Cloud sync in Factorio properties in Steam library (unless you need it)

[rawdatadaniel]

I encountered this same issue when my machine shut itself off in the middle of a save because it overheated.

upon launching the auto saves my hotkeys and settings in general are gone

This part of the issue is particularly problematic, because it means I can't change any of the "requires restart" graphics settings, which I need to do to prevent my machine from overheating again. I haven't tried deleting my configs or anything like that yet - probably one of the above suggestions will allow me to get playing again.

[Rseding91]

I encountered this same issue when my machine shut itself off in the middle of a save because it overheated.

upon launching the auto saves my hotkeys and settings in general are gone

This part of the issue is particularly problematic, because it means I can't change any of the "requires restart" graphics settings, which I need to do to prevent my machine from overheating again. I haven't tried deleting my configs or anything like that yet - probably one of the above suggestions will allow me to get playing again.

Changing software settings to prevent overheating is the wrong way to fix a problem. Fix the overheating problem by fixing the cooling on your computer.