This is going to start as a whinge. I made a save, of course, before updating mods. And it seemed everything was fine. It took 2 days for the ramifications of having the solar array on three of my planets deleted, as I have redundancy and it wasn't doing anything. But I'm rebuilding my primary base, and can't make 10k advanced solar panels easily.

There is more broken, but this one is the infuriating one as I don't know how I will fix my planets without the editor.

How many save-breaking updates are yet coming? Is this from this mod or from one of the ones it is based on?

There are probably going to be some updates coming that change a few recipes here and there, but something like "losing thousands of solar panels" (or, in fact, losing any entities at all) should generally not happen... ever. I strongly recommend not continuing to play on a save that shows a large number of "removed entities" without checking to see if that's supposed to happen.

In the case of solar panels, I'm not aware of any issues or changes that would have affected them at all. The only disappearing entity issue I'm aware of was due to an interaction between 248k's changes and certain functionality in K2, but that particular issue would only affect roboports and some assembling machines whose prototype names have changed, neither of which applies to advanced solar panels.

If you're willing and able to share a save file from before the update, I might be able to figure out what happened; failing that, a list of what mods you have active might help.

I am willing to, but not sure how able to, given its size.

Correction. Solar panels 2.0

I have an idea that it may have been due to solar and accumulator buff, as I had an issue with a ghost of an accumulator which would not place, as though it was replacing entities instead of applying the buff in some other way. And, yep. Gone. Only found out when I had 32 buildings destroyed by meteor, and went "huh, it can't be out of ammo yet, should be good for a week of real time at least" But no, it was out of solar panels, and the emergency reactor which was supposed to only power the umbrella and meteor defenses in case of power loss had chewed through ALL the fuel. I can resupply it (them), though my planets will take damage in the meantime. Or I can load back 2 weeks.

Normally I'd never save over an old save but these are so big, I can't store hundreds of them. After a day I thought everything was fine, and on Nauvis, it was (except my very pointless lithium hydroxide and battery infrastructure - but that's a minor inconvenience).

Anyway, if the 2.0 solar panel (which I believe is from 248k) explains it, then no need. Otherwise, can you tell me where I can plonk a quarter gig file?

And I could potentially do you one better than a list. I have a backup of my 'last working' mods folder. But that is 1.5 gigs.

If I had the save from before I updated too, I'd just blueprint my base and revert back, and postpone the update. But sadly I did save over than and only have the saves from 2 weeks ago and prior

Normally I'd never save over an old save but these are so big, I can't store hundreds of them.

Well, for that I gotta go back to what I said before - if you load a save file, and it has a big "entities removed" line, that's a sign something is wrong.

Anyway, no need for the files, you gave me the clue to figure it out - it's the same issue with a different mod. Solar Productivity makes 50 copies of every solar panel with different names, there was no migration for them, they went poof.

Solar Productivity does have commands to help deal with this - /sp-transition replaces all the modified panels with stock ones (though with thousands of them it would take some time) and then /sp-update to restore the modified solar panels after updating - but, uh, if you already overwrote all your pre-update saves, that's not gonna help.

So. Not a bug, just a bad combination of interactions... but I'm not particularly happy with the state of things. The migrations system is supposed to handle things like this, and it does... for the regular entities, but this entity copy thing is another matter. There ought to be a better way of handling that than there is now. I just don't know what it is.

Yeah, well clearly some of this was my own fault, quite aware of that. I am building my Nauvis base and will be for the next 50 hours. No need to go off world, production is shut down. Like I said, real estate is too premium, I had to upgrade the smelting, now I do the production downstreem.

Maybe I'll see how much rubbish would be left if I Blueprint my base and copy it over the 2 week old file. I'd lose millions of fluid but that can be replaced.

How does this command work exactly? Where and when to type it with respect to updating the mods? And do I need to run it on each force or will it work for the whole save?

And will this void achievements? Because if so, I may as well just use the editor to replace the panels.

And, thanks for the help

EDIT- I have taken the hit and spent time and saved resources reviving my bases to a grey-mode safe state. So, I will check for removed entities in the future, and keep last couple of saves.

In case it does happen again, can you confirm that I use the first command prior to update/ after re-downgrading. Then save. Then update. Then use the second command?

In case it does happen again, can you confirm that I use the first command prior to update/ after re-downgrading. Then save. Then update. Then use the second command?

That's correct.