Game stops: "unknown object type serialised by server"

Somewhere in this map is an game-halting error. Screenie is when we enter and no problems yet occur. I players through about a quarter of the map, killed a number of things, and encountered this (needed to force close the client).

Cannot decipher from the client end - there's nothing on screen that indicates something is up.

EDIT: Replication log
(Using Frantfurt server)
Portal 1: Enter map clean counter clock-wise, crash after 25%.
Portal 2: Enter map, crash after ~5 steps.
(Clean out Dried Lake, no problems with instance)
Portal 3: Clean eastwards across map. Crash after crossing most of the map(?).
...seems restricted to this particular instance in question.

I got the same bug, first when I opened a Strongbox the game instantly froze and after restarting the area is broken and it seems to crash when I try to get close to that box. There is also a Tora den close by. I get the same error message and have to shut down the game.

I filed an ingame bug report, the number is: 3,273,825,597 but obviously that is when the game is still running.

Edit:
I got the bug in mud flats in cruel difficulty on the Frankfurt server in Essence league.

Both of you guys. Look in your client.txt file (POE install dir/logs folder. Look for the time stamp when you crashed, if you remember. What, if any, error is thrown? What Instance IP?

Mal, actually, yours is slightly different (Different area etc), I'd make a new thread since yours centers around a lockbox.

2016/09/30 07:38:52 311662562 6d [INFO Client 1772] Tile hash: 590653636
2016/09/30 07:38:52 311662562 6e [INFO Client 1772] Doodad hash: 973846560

Perhaps that helps, but I can't see anything different from other areas and nothing at the time of the crash.

Error message: "unknown object type serialised by server" (thread title)

After the last crash I don't think it has anything to do with the strongbox, it was just a coincidence that it happened when I opened it. The fourth crash happened when I was quite a bit away from the box and moving away from it, while fighting an Essence monster (that wasn't active during the other crashes).

I have the same issue when I entered normal Battlefront. Same exact message. Started after I activated an essence near the entrance. Every subsequent time I entered the zone and made a few steps the game would crash. Creating new instance fixed the problem.

Same issue, opened Mesa map and upon moving a few steps it just bopped. Hasn't ever happened before 2.4.0h

2016/09/30 07:59:54 2761984 cd [INFO Client 4524] Connecting to instance server at 146.0.225.167:6112
2016/09/30 07:59:54 2762015 111 [DEBUG Client 4524] Connect time to instance server was 31ms
2016/09/30 07:59:54 2762328 6d [INFO Client 4524] Tile hash: 1156353097
2016/09/30 07:59:54 2762328 6e [INFO Client 4524] Doodad hash: 2105580368
2016/09/30 07:59:55 2763140 903 [DEBUG Client 4524] Entering area MapAtlasMesa

Same Error Messeage here.
I entered the Portal of a Master Mission but it crashes after a few Steps.
On relog the Portal is still there but it just crashes again when I enter and try to leave the first Room.

Same problem here, i opened an Atoll map, made few steps and got this error too.. i tried to go again in the map but it keeps showing.



Edit for image!
P.S Game crashes at the exact same spot as if its interacting with something that gives that error ( object or i dont know what)

I have this error too

Me too...
Done about 10 maps which were ok.
Then i started vaal side area and the error freezes my game. Force close via task manager necessary. Tried 3 times to enter that area, all 3 times crashed.

Edit: Tried another area and the same thing happened. But this time it was a bit different. This time the game let me go a bit more into the map and started crashing mid way to the end of the map. Always crashes at the same spot. Almost as if I was approaching something and when close enough to it, the game crashes.