Experiencing "small-pox"!

[TheMurderousCricket 5,048]

It's the third or fourth time in about 1.5 year that I run into this problem and I'd like to consult with you before I push the panic button.

I noticed that sometimes, some of the props I put in my cities disappear for no good reason. An event I dubbed "small-pox". 

Recently, an entire coastal MMP park has been wiped out of my city. It was very surprising. The props involved in this event include vanilla Maxis trees, Scrub Brush Mod, ALN files (grasses, and other low-growth), PEG Pines and CP trees (like redwoods, subalpine firs etc.) Pretty much every type of MMP there is...

Interestingly, the props disappeared from just the southern coast of my city, while the objects to the north remained just the way they were.

I was able to restore the city from my backup and the props are back where they were, so I don't think this is a plugin conflict.

The props located on lots remain unchanged regardless.

Any ideas as to what is happening with my game?

[rsc204 21,807]

Sounds like it could be Prop Pox, does the problem keep returning to the same city after restoring from a Backup? PropPox usually doesn't show it's affects until the Prop SubFile (a part of the game's savefile), gets too large and needs to use a different system to continue. At this point invalid data which is preexisting, starts to become a problem, such that parts of the Prop data get overwritten causing data corruption. Essentially any invalid entries end up throwing off the data-sequence which starts a domino effect, where the problem simply gets worse with each subsequent save.

SC4Fix r7 can fix the corrupted data, so I would advise installing this and it should correct the damaged save file before anything get's permanently broken. It can't bring back your props, but it should prevent the same thing happening again after restoring a working backup.

[TheMurderousCricket 5,048]

2 hours ago, rsc204 said:

Sounds like it could be Prop Pox, does the problem keep returning to the same city after restoring from a Backup?

So far it hasn't. I had SC4Fix installed prior to backing up too. I saved & exited the city thrice so far and everything is back to where it was.

3 hours ago, rsc204 said:

PropPox usually doesn't show it's affects until the Prop SubFile (a part of the game's savefile), gets too large and needs to use a different system to continue.

How large would that be? I don't have any save file in that region greater than a total of 4.5 mb...?

3 hours ago, rsc204 said:

It can't bring back your props, but it should prevent the same thing happening again after restoring a working backup.

Understood. But do I have to complete the restore procedure described on the SC4Fix download page after backing up, or is it not applicable in a backup scenario?

[rsc204 21,807]

Well without going into laborious technical detail, if restoring a file from a backup, it shouldn't develop Prop Pox since the data gets written differently after saving with that fix installed. So far as I can tell from the instructions, this was an attempt to fix an already affected tile, so the restore procedure shouldn't be required. Then again, what the hell why not do it just in case, if switching the Prop detail level somehow refreshes the save data of a city, then nothing bad can come from doing this.

You should verify that SC4 Fix is correctly loading, switch out of the game and hover over the taskbar, where you should see it mention SC4 Fix as part of the (running) app name. Just to be safe, .dll mods should be placed in the root Plugins folder inside the install folder, not the usual Documents\SimCity 4 one. They need to load before other mods and if placed in the User Dir Plugins folder, that won't always happen.

If it's definitely working, but your cities keep having problems, that would suggest you might have another problem, although save file corruption is still the most likely explanation. But if your backup keeps getting borked, the trigger must remain in that backup file somewhere. I think you should check your save file with Savegame Explorer, to see if it is marked as Poxed or not, do this for both the broken and working backup file, just to get some data. Something doesn't add up somewhere in this.

[TheMurderousCricket 5,048]

24 minutes ago, rsc204 said:

nothing bad can come from doing this.

You think so?

I just followed the "restore" procedure in my ok backup... and the props are gone! 

A weird thing is that the restored backup can be saved over and over with no consequences. It seems that applying the "fix" procedure actually breaks it! I can't wrap my head around it...

24 minutes ago, rsc204 said:

You should verify that SC4 Fix is correctly loading

It runs correctly. All good here.

Strange!

 

[CorinaMarie 29,580]

I have a silly idea.

It sounds like from your first post that it's custom content MMPs and Maxis too which disappear so this won't be it. But could it be just the Maxis trees that start small, grow tall, and then cycle back to tiny?

[TheMurderousCricket 5,048]

4 minutes ago, CorinaMarie said:

I have a silly idea.

It sounds like from your first post that it's custom content MMPs and Maxis too which disappear so this won't be it. But could it be just the Maxis trees that start small, grow tall, and then cycle back to tiny?

Nope. They vanish entirely (upon being "fixed" ).

[TheMurderousCricket 5,048]

Sorry for double-posting, but I have just discovered something rather interesting.

The issue I experienced has nothing to do with the prop pox but a rather different (new?) problem which is indeed more of a "small-pox".

It most likely involves MMPs which are placed on top of other lots.

I ran an experiment on a new, undeveloped city tile. I have plopped some Paeng's grass tiles, after which I plopped some MMPs on top of it - which I frequently do. Then, I placed exact same set of MMPs nearby - on a barren ground:

Then, I started to follow the procedure that you normally use to fix a poxed city. But upon reaching this step...

"3. Open the offending city tile..."

...my test area has already turned into this:

The MMPs plopped on a barren ground remained while those planted onto the Paeng's grass have vanished.

Interesting. It looks like the fix might be a double-edged sword in this peculiar setting - it fixes the prop pox bug, but somehow removes all of the props that are located over lots. Try it yourself - I wonder if you can reproduce my findings!