Corrupted saves / error code after EA App update (tried all standard fixes)

you seem to have an issue with a milestone that was on a cc that you removed from the game.

Try this mod: https://www.patreon.com/posts/mod-milestone-81237568  (File 2: CC/Mod Object Fix).

It's a script mod so make sure to enable those. You can remove the mod once you fixed the game.

Hi crinrict​ 

Thank you, yes, I have LastException file, and after I delete the file, the issue is still there and creating another LastException file after running the game. Here is the file's text 🙏:

<?xml version="1.0" ?><root>

<report><version>2</version><sessionid>1a33bdbf4688a9fe6a0a0037</sessionid><type>desync</type><sku>ea.maxis.sims4.15.macarm64</sku><createtime>2026-05-17 19:53:20</createtime><buildsignature>Local.Unknown.Unknown.1.124.55.1230-1.200.000.708.Release</buildsignature><categoryid>developmental_milestone_tracker.py:1130</categoryid><desyncid>1a33bdbf4688a9fe6a0a0037</desyncid><systemconfig/><screenshot/><desyncdata>Exception raised while processing zone spin up sequence: 'Object not found: 0x6d57b' (KeyError: 'Object not found: 0x6d57b')&#13;&#10;Traceback (most recent call last):&#13;&#10;&#13;&#10; File "T:\InGame\Gameplay\Scripts\Server\areaserver.py", line 130, in wrapped&#13;&#10; File "T:\InGame\Gameplay\Scripts\Server\areaserver.py", line 126, in finally_wrap&#13;&#10; File "T:\InGame\Gameplay\Scripts\Core\sims4\utils.py", line 157, in wrapper&#13;&#10; File "T:\InGame\Gameplay\Scripts\Core\sims4\utils.py", line 175, in wrapper&#13;&#10; File "T:\InGame\Gameplay\Scripts\Server\areaserver.py", line 383, in c_api_client_connect&#13;&#10; File "T:\InGame\Gameplay\Scripts\Server\zone.py", line 612, in do_zone_spin_up&#13;&#10; File "T:\InGame\Gameplay\Scripts\Server\zone_spin_up_service.py", line 1881, in update&#13;&#10; File "T:\InGame\Gameplay\Scripts\Server\zone_spin_up_service.py", line 924, in on_update&#13;&#10; File "T:\InGame\Gameplay\Scripts\Server\zone.py", line 1076, in on_all_sims_spawned&#13;&#10; File "T:\InGame\Gameplay\Scripts\Server\zone.py", line 1142, in _set_zone_state&#13;&#10; File "T:\InGame\Gameplay\Scripts\Core\sims4\callback_utils.py", line 158, in __call__&#13;&#10; File "T:\InGame\Gameplay\Scripts\Server\developmental_milestones\developmental_milestone_tracker.py", line 274, in start_milestone_tracker&#13;&#10; File "T:\InGame\Gameplay\Scripts\Server\developmental_milestones\developmental_milestone_tracker.py", line 733, in _activate_available_milestones&#13;&#10; File "T:\InGame\Gameplay\Scripts\Server\developmental_milestones\developmental_milestone_tracker.py", line 565, in activate_milestone&#13;&#10; File "T:\InGame\Gameplay\Scripts\Server\developmental_milestones\developmental_milestone_tracker.py", line 315, in process_evaluation&#13;&#10; File "T:\InGame\Gameplay\Scripts\Server\developmental_milestones\developmental_milestone_tracker.py", line 1225, in send_all_milestones_update_to_client&#13;&#10; File "T:\InGame\Gameplay\Scripts\Server\developmental_milestones\developmental_milestone_tracker.py", line 1130, in _get_milestone_update_msg&#13;&#10;KeyError: 'Object not found: 0x6d57b'rtim=0&#13;&#10;Client Session Time: 22.06&#13; &#10;Num Save Errors: 0&#13; &#10;Num Load Errors: 0&#13; &#10;Current Game State: 0x96d01090&#13; &#10;LoadingScreenActiveFlag: 1&#13; &#10;Origin Version: 13,700,0,6213&#13; &#10;Modded: True&#13; &#10;SystemInfo: Mac OS X Version 26.3.1 (a) (Build 25D771280a) GPU: Apple M1 Max macOS Metal driver 0.0.0.0&#13; &#10;Architecture: arm64&#13; &#10;&#13; &#10;</desyncdata></report>

</root>

Hi VibeBase​ 

Do you have any LastException files in Documents\Electronic Arts\The Sims 4 ?

• Delete the ones you have
• Trigger the error again
• Check if new ones are created
• If that is the case, please copy/paste the content here. You can open the file with any text editor.

Deleting the file won't fix your issue. Posting the info is meant for troubleshooting.