Minecraft Forums

(Read the title.)

Important things to note:

• This is happening in 1.10.2. The only help I could find for this issue is for Minecraft 1.3-1.5-ish.
• It is a singleplayer, creative world. My client is unmodded, although I do have Optifine.
• A fix for this was listed in a Minecraft 1.3 forum, saying to load a different world (forcing the previous one to save). It seemed to work on blocks, but not entities or block entities (i.e. villagers and command blocks).
• I have what I refer to as a "Craptop". I run Minecraft on low visual settings, I have terrible RAM (opening too many tabs in Chrome crashes my Minecraft), and I have < 7GB left of space on my computer.
• I have migrated this save file to other computers before, so as to work on the world, but the error occured after I moved the file back to my computer, after some time. This error hasn't occured on the world, or any other world, until now.
• Blocks and block entites won't save, but my inventory and location do without fail, every time.
• EDIT: I have confirmed that it is not the world that won't save, but individual chunks. I can tell, because whenever I unload a chunk and return to it later, my progress has reverted. This is...very bizarre. Also, villagers I spawn in these chunks are deleted, even though I have the PersistanceRequired tag on them (although I don't think that's really important).
• EDIT AGAIN: By running Minecraft in Compatibility Mode for Windows 7, the blocks seem to save now. This was a fix for the 1.3 version of this bug.
• However, I have 2 villagers that I spawn in a guard tower near a village. These 2 villagers despawn whenever the chunk unloads, even with the PersistanceRequired tag. Yet... the villagers in the village, and the villagers I spawned with the same command near the spawn chunks, never despawn. What the heck is happening!?
• ANOTHER EDIT AGAIN: The compatibility mode thing doesn't actually work. Blocks appear to save, but don't when world is closed. Entites despawn when chunks unload or when world is closed. Spawn-chunk entities despawn as well. This only applies to entites summoned through command blocks, previously present entites don't despawn.
• OKAY, THIS ISN'T FUNNY ANYMORE: Whenever I place blocks, then save and quit the map (i.e. go back to title screen), the blocks I place are saved fine. But whenever I place blocks, then use the summon villager command, both the blocks AND the villager despawn. I confirmed this in 3 different worlds. Also, using spawn eggs to summon entites works fine, but if I summon the villager and the egg, BOTH mobs despawn. I think that my computer is doing some really bizzare things... That, and the command might be messed up in weird ways.

Please help!!!

Bump. Please, does anyone know how to fix this?? Or even why it happens?? ANY help would be greatly appreciated!

whenever individual chunks have problems, this usually means that the chunk is corrupted on disk. At that point the chunk can't be truly modified, i.e. it reverts on reload.

there are tools that can repair damaged saves...

Try these things.

Reinstall Java

Reinstall minecraft

Free up hard drive space

Run minecraft with 1GB of ram

Thanks to both of you! I'll try these and see if anything works

Any luck?