So there you are, on your way to someplace cool. Minding your own business. Then, suddenly, the screen goes black and Windows throws an error. As your screams echo into the void, one thought crosses your mind. "I haven't changed anything here recently." So what happened? Why did the game just up and crash? Undaunted, you load back up and proceed to the same area again, only to be met with the same fate. Why does this keep happening?

The answer is probably simple enough. You've got a corrupted spawn point. If you'd like to find out what mod this came from, rather than ignore the error by hiding in the testing cell for a week, read on.

So I hear you ask, how does one go about tracking this down? It's not as hard as it may seem, but it does take a bit of patience and some reference material to make it easier. Here's a list of things you'll need to start your hunt:

A copy of http://www.tesnexus.com/downloads/images/23939-1-1240451419.jpg - this is a map with cell blocks listed.
A copy of TES4Edit, or Gecko.

You'll need to start by using the console and having it display debug information as you're walking. Open the console with the ~ key, then type in "sdt 0" and hit enter. Then type in "tdt" and you'll see a bunch of information on the screen. The stuff we're concerned with here is the PC Cell data. Slowly approach the spot where the game crashes, keeping an eye on what cell it reports you are in. A corrupt spawn will crash the game very shortly after the cell location updates, so be ready to write it down.

Once you have the proper cell handy, you'll need that big map. Look closely, you'll see small white numbers. These are cell coordinates. You can't use the cell the game crashed in, you have to keep in mind that data ahead of you is being loaded into memory. With a default ini file for the game, this is usually two full cells. So for example, if you're in cell 8,33 and you notice the game crashes upon entering cell 8,34 going north, then you'll actually want to look up cell 8,36 on the map file because that's the one that's two cells ahead of you. To be on the safe side, also keep cell 7,36 and 9,36 in mind because they're also being loaded into memory.

Now you need to open up TES4Edit. Allow it to load whatever your current load order is, the mods should all be checked. While you wait, look at the map, the cell you're after will be in one of the large colored green blocks. These are storage markers for the internal data of the file. Note that cell 8,36 is in Sub-block 1,4 of ExtCellGroup 0,1. When TES4Edit signals it's ready, open the branch for Oblivion.esm. Scroll down to the Worldspace block, and open that branch. Open the worldspace you want, in this case Tamriel. Notice the block sections under it. Find 0,1 and open it. Under that will be several sub-blocks. Open 1,4. On that list of cells will be cell 8,36 "BrumaTamrielExterior07". If you highlight that cell, the right pane of TES4Edit will list all the mods which are affecting that cell. Take note of which ones are listed. While you're in here, check cell 9,36 as well "FGC05BanditCampTEMP". You'll also want to find cell 7,36 - you should be able to figure out how to locate it using the big map file.

So in the example, lets say you notice that Unofficial Oblivion Patch, TIE, Crowded Roads, and Open Cities all touch cell 8,36. Since we're looking for corrupt spawn points, it doesn't make sense to suspect the UOP because it doesn't place any (though it may move some). It also makes no sense to suspect Open Cities, because it does not use spawn points. This leaves you with two possible suspects: TIE and Crowded Roads. You may find the same set of mods also touches 7,36 and 9,36.

In order to confirm suspicion, close out the programs. Deactivate one of the two mods and load the game. Walk toward the crash point. If it dies again, try deactivating the other. Keep doing this until the game stops crashing as you cross the cell boundary. Once you can make it through without crashing, you can exit out and reactivate your other mods, then load the save without the offending mod. Cross your cell boundary, then save again and reactivate it.

You should take care to note whether it is safe for your game to deactivate a mod with spawn points. Crowded Roads is, since you are unlikely to be holding important items from it. TIE should be safe to disabled for a short period, though your item stats will revert to vanilla during this time. You should only keep the crashing mod disabled long enough to be sure the game won't crash.

Don't bother the mod author with reporting a corrupt spawn, there's likely nothing they can do about it. It's a general annoyance of the game. Eventually one comes up. The above long drawn out procedure is also unlikely to be necessary unless your respawn timers are very long, or you're playing mods which prohibit the usual tactic of hiding in the testing cell for days on end getting it to reset. This will allow you to identify the suspect, and once you're familiar with navigating TES4Edit and reading console data, this will almost certainly be faster than interrupting your journey with a trip to the testing cell. The added benefit of this is that you won't have to remember how you got to where you were.

The above was inspired by my own first run-in with a corrupt spawn that was traced to Crowded Roads Revisited. A clean save of the mod removed the problem, allowing my poor character to continue his trek up the mountain to Bruma.

If only it was so easy when the spawns are from MMM or OOO.

The most annoying thing about corrupt spawns is that no matter how clean and polished your game is you are not safe.

Another method to solve the problem can also be to load an earlier save, before the corruption occured.

Also, it may be useful to know how to tell this kind of crash apart from other crashes.
The crashes are in my experience slow crashes, with the screen going black, not instant CTD or the game freezing. Sometimes things may look fine when playing, but then the game crashes when saving or loading a new cell, as it purges the bad data.

Thanks Arthmoor!

This looks to be the info I am http://www.gamesas.com/bgsforums/index.php?showtopic=1032357 for. Annoying null-pointer reference crash...

Well, your crash was not actually due to a NULL pointer. That's just what WEOCPS told you.

Your real error was at 0x001e66b7, which is what WEOCPS was suppressing, but suppressing it clearly didn't help as it simply led to another crash elsewhere that the plugin could not stop.

In my case, it was consistent at 0x0024dfb6. Doesn't mean anything to me really, and WEOCPS likely can't recover from a corrupt spawn anyway. Besides, it's generally not a good idea to try and dodge crashes anyway. Corrupt data can sneak by if the recovery manages to keep the game running.

If your crash is due to a corrupt spawn, and your description of it tells me probably yes, then finding it with the process I outlined shouldn't be overly hard. Assuming it doesn't lead you to a mod you can't clean save out of

This is something WindomEarle warned may be a side effect of using weOCPS. If this is the case it kind of defeats the purpose of using it- to keep playing after a weOCPS recovered crash. :shrug:

Will try out your suggestions and report the result.

thanks for the great article.

but what actually *is* a corrupt spawn really? ie. does anyone know how oblivion screws up a spawn? I'm guessing we're not talking about spawning some creature with faulty meshes, but an actual failed spawn that the engine then chokes on somehow?

:celebration: I found and fixed the problem! Lost Spires has some influence on -13, 2 (DerelictMineExterior) and deactivating it solved the crash. FYI, the only other mod I use that effected the cell (other than OB .esm and the UOP) was Tamriel Travellers.

You missed one minor step in your article: I took note of this only because this was the first time I used TES4Edit.

Thanks again for the help. :thumbsup: :trophy:

I'll now have a go at cleaning Lost Spires and reinstalling.

But don't forget that uninstalling a quest mod means you will lose all progress in that mod and all items from it...

The damage already seems to be done. I didn't actually uninstall only deactivated but my warlock torch (and I assume everything else) is gone. I've already finished the quest but have kept it activated because the mod has some very nifty items.

I'll be happy to eventually play through it again.

Oops, well. In the case of my example I wanted Tamriel, but yeah, open whatever worldspace you're looking for

And Lost Spires isn't one of those I would have done that sort of thing with. But as long as you don't mind and it let you get on with things without too much trouble, ok.

The only flaw in your logic I see is that you mentioned in your other post that you couldn't go from -13,2 into -13,3 (assuming northward movement here) so you should actually have been looking at -13,5 for the cause. Corrupt spawn points trip themselves as soon as they load - if removing something in -13,2 fixed your issue it wasn't a corrupt spawn. You were already in that cell.

I think your referring to http://www.gamesas.com/bgsforums/index.php?s=&showtopic=1032357&view=findpost&p=14953461: What I meant was that i had determined the problem to lay within the -13, 2 to -13, 3 or -14, 2 to -14, 3 range. I tried approaching the area from 8 compass directions and was not able to actually enter any of this range of cells, Ex moving NW from within cell -11, 0 the game would crash as soon I reached the cell boundary, with -11, 0 still showing with tdt as the game minimized and the Windows error message appeared. Also, this was just an estimate- I just knew the approx range of cells. The crash was always very abrupt, with or without weOCPS.



Are you saying I shouldn't try to clean LS or that IYO loosing quest progress in LS wouldn't be worth deactivating it?

Oh, you should definitely run it through cleaning, it's got dirt and LOTS of deleted references. And if it uses spawn points, it could have had a corrupt one just like anything else. I just wouldn't have deactivated it if I'd already played through. I would have gone around the area, or used the testing cell method.

Any spawn can go corrupt, including vanilla ones, and if you get one of those go bad, you don't have a choice but to use the testing cell method to fix it.

Testing cell method means, say, coc to center and wait out respawn right? I did this and, when I first got the crash near Skingrad (at ~100 hrs on this character which is now over 400 hrs) it worked. Something was different this time.

As far as losing progress in LS, I'll take it as a learning experience re the value of cleaning mods (if indeed that would have prevented my problem), which I have not yet done at all.

Cleaning LS would probably have been helpful, as my cleaned copy has no edits anywhere in the sub-block that -13,2 would occupy.

And yes, coc testinghall. It's a common hideout for waiting the 4 days for spawn data to go away. Then just coc weye to get back out. Main reason I don't like the method is because you have to abandoned your journey wherever you are. When you don't use fast travel, it's a pain

I just like setting a mark&recall point from LAME, then teleporting back to frostcrag to hide under the covers until it goes away
I'll give this a shot next time, though. Could be fun.

Having a "zone of corruption" in my game was seriously interfering with my enjoyment... as anyone who has persisted with OB knows, the journey is fraught with peril. oo:

Well I actually found the specific problem by loading only The Lost Spires.esp in TES4Edit and looking at its worldspace activity. 2 "DeadSkeleton"'s http://img215.imageshack.us/img215/2637/culprit1.jpg and http://img213.imageshack.us/img213/6850/culprit2.jpg. No idea how they got there... maybe the dead skellys outside of Derelict Mine where somehow modified.

Automatic (3 stage) cleaning with TES4Edit has removed these skeletons and fixed the problem. And, by simply re-enabling the LS .esp and loading my last save before I disabled it, all my progress in LS is preserved! No items (that I'm carrying) have been lost and I'm still Headmaster (next rank DUMMY).

I now feel that I can conquer all obstacles OB can throw my way! :ninja: :lmao:

This is a very interesting thread.

Would another alternative be to use the CS to create a temporary mod to delete the offending spawn point, placing this temp mod later (or last) in the load list? I'm thinking this could be possibly useful for those situations - like quest mods - where deactivating is undesirable.

I don't think deleting the spawn point would help as the creature(s) it spawned are aready in the save game. But temporarily deleting the creatures from the mod, instead of deactivating the whole mod, would probably work.

*bookmarks*

I suppose that would probably work, I didn't bother to track my particular problem down to an individual spawn point. Unfortunately in my case that would have been almost impossible as Crowded Roads fills the game with them on nearly every stretch of road imaginable. I would have had to delete probably 30 or so of them. No wonder I had to lower its spawn chance to 2%

In earthling's case though it wouldn't have helped, there was no spawn point issue in -13,2. That was apparently a case of a bogus delete that shouldn't have been in the file. Those usually don't cause problems, but they can.

Hello,

*very newbie question here* so please bear with me : ) If it isn possible to differ a "normal" spawn point from a bugged one in the savegame, wouldnt clean all spawn points from the suspicious cell from the savegame fix the issue? There isnt any tool that could do that, like Enchanted Editor for Morrowind could? (not sure if it specifically allowed to delete spawn points, but it allowed several savegame edits, if Im not mistaken)
Thanks

There is no savegame editor for Oblivion.

Excellent article! This should help a lot of bug-hunters. :tops:

Would indeed be interesting to know what sorts of things cause corrupt spawn points (other than a null pointer in the spawn list, that is). Does this actually happen with spawn lists or only placed actors?

One thing I didn't quite follow. Does "sdt 0" tell you which block and sub-block to look in? If not, you're in for a long hunting process unless you first apply a filter in TES4Edit to flatten the cell blocks. You can then sort them so they are listed in sequence, making it vastly easier to find the one you're looking for.



That would be sweet, but Oblivion uses a different savegame format that's not at all similar to plugins (as it was in Morrowind). Sadly, this new format has not been decoded yet, so we have no general-purpose savegame editors yet.

Oh, I didnt know that : ( Wrye Bash seems to touch some aspects of the savegame, like repair factions, repair abomb, repair hair.. so what is known so far isnt enough for a "repair spawn"? : )

Well in my particular case I'm assuming it was a corrupt spawn placement because Crowded Roads does not do any direct NPC drops. It's all spawners.


"sdt 0" is only going to give you the cell, I don't think any of the debug modes that provide it will give you more than that. That's why I linked in the jpg with all the cell blocks on it. Makes it pretty quick to find that way.