I was seeking a way to save my old vaults so that I could start new ones without losing my old ones.

I got some advice here to make a copy of my vault save files. Ok... I did that. That was the easy part.

Then I deleted a vault.

Then I replaced that vault's save file and restarted..... and the vault is still gone.

Now that I have my lost vault's save file, how do I get it reactivated to restore my lost vault? Apparently just dragging the .sav file back into position and overwriting doesn't work.

Wait... I restored a .sav file to a vault that wasn't there anymore; that is, each vault has two files, the vault itself and it's save file. Do I have to start a new vault first, and then replace that new vault's save file with my old saved file to change the new vault into my old one? Will that work??

EDIT/UPDATE: Nope, that didn't work.

That's the method I've always used. I've moved vaults from my GF's phone to our tablet, tablet to my phone, one phone to another phone, etc. It's always a simple copy of the .sav files into the \Phone storage\Android\data\com.gamesas.falloutshelter\files\ folder and they just show up in the vault list.

Maybe I should stop trying to help people on here, my sure-fire methods don't work for anyone else.

As far as I can tell, it should have worked.

Maybe the trick is to copy both the vault AND the vault.sav files, and replace them both? Is that what you do? I only did the .sav files.

Well, no biggie. That vault had problems anyway, which is why I selected it for this experiment.

What is this other vault file you have? I've got Vault1.sav(the actual vault) and Vault1.sav.bak(the backup copy the game automatically creates), but nothing else. I just move those two files around, though the .bak shouldn't be necessary(it didn't even exist until v1.2).

When I copied the vault.sav file, the new copy was automatically called vault.sav.bak. I didn't get an option to just make a .sav.

When I dragged the .sav.bak over the .sav I wanted to change, it asked me if I wanted to replace the file and I said yes.

That sounds to me like it should have worked.

I'm tempted to copy both the vault AND vault.sav files and see if replacing both will restore a lost vault, but I don't have any more expendable vaults handy. I guess I'll make a new one and experiment with that.

Oh, that could be the issue then. If you only replace the vault.sav.bak nothing will happen. The game doesn't read anything from that file when you're playing, it's just there in case the main vault.sav gets corrupted. You can rename a vault.sav.bak to just vault.sav, and then the game reads it as a playable vault.