Im just after many hours of investigation to make my server start after the 2.4 update, and i finally made it work, so wanted to share in case somebody got a similar headache:)
So in the logs I had such messages as:
[2021.04.24-14.16.25:695][ 2]Persistence:Warning: Code: Cannot find property "BuffAddedByModKit" in class "PersistentHumanoidNPC_C"!
[2021.04.24-14.16.25:695][ 2]Persistence:Warning: Code: Cannot find property "BuffAddedByModKit" in class "PersistentHumanoidNPC_C"!
[2021.04.24-14.16.25:695][ 2]Persistence:Warning: Code: Cannot find property "BuffAddedByModKit" in class "PersistentHumanoidNPC_C"!
[2021.04.24-14.16.25:699][ 2]Persistence:Warning: Code: Cannot find property "BuffAddedByModKit" in class "PersistentHumanoidNPC_C"!
[2021.04.24-14.16.25:699][ 2]Persistence:Warning: Code: Cannot find property "BuffAddedByModKit" in class "PersistentHumanoidNPC_C"!
[2021.04.24-14.16.25:699][ 2]Persistence:Warning: Code: Cannot find property "BuffAddedByModKit" in class "PersistentHumanoidNPC_C"!
[2021.04.24-14.16.25:700][ 2]Persistence:Warning: Code: Cannot find property "BuffAddedByModKit" in class "PersistentHumanoidNPC_C"!
[2021.04.24-14.16.25:707][ 2]LogMemory:Warning: Freeing 33554432 bytes from backup pool to handle out of memory.
[2021.04.24-14.16.25:707][ 2]LogMemory:Warning: MemoryStats:
AvailablePhysical 80982450176
AvailableVirtual 140731536654336
UsedPhysical 5294252032
PeakUsedPhysical 5877403648
UsedVirtual 5547728896
PeakUsedVirtual 5904441344
[2021.04.24-14.16.25:707][ 2]FMallocBinned2 Mem report
[2021.04.24-14.16.25:707][ 2]Constants.BinnedPageSize = 65536
[2021.04.24-14.16.25:707][ 2]Constants.BinnedAllocationGranularity = 65536
[2021.04.24-14.16.25:707][ 2]Small Pool Allocations: 2643.975403mb (including block size padding)
[2021.04.24-14.16.25:707][ 2]Small Pool OS Allocated: 2690.750000mb
[2021.04.24-14.16.25:707][ 2]Large Pool Requested Allocations: 2491.281677mb
[2021.04.24-14.16.25:707][ 2]Large Pool OS Allocated: 2510.437500mb
[2021.04.24-14.16.25:707][ 2]Requested Allocations: 2491.281677mb
[2021.04.24-14.16.25:707][ 2]OS Allocated: 2510.437500mb
[2021.04.24-14.16.25:707][ 2]PoolInfo: 2.812500mb
[2021.04.24-14.16.25:707][ 2]Hash: 0.125000mb
[2021.04.24-14.16.25:707][ 2]TLS: 0.500000mb
[2021.04.24-14.16.25:707][ 2]Total allocated from OS: 5204.625000mb
[2021.04.24-14.16.25:707][ 2]Cached free OS pages: 0.000000mb
[2021.04.24-14.16.25:715][ 2]LogWindows: Windows GetLastError: The operation completed successfully. (0)
After making certain without mod on single player it isnt the base game, I started tracking with our ~20 mods :).After a lot of time It turned out its the chareditlite mod which was the cause. Also during all these tests I noticed that after runing it once without chareditlite, you can then resubscribe again and it will work, I presume some problematic data are being corrected duirng the start without chareditlite.
So finally the solution:
1- Removed chareditlite from the server.
2- Reloaded the backup I made just before the update.( thank god i made it lol)
3-Started the server and started the client just to see it shows up in the server browsers, didnt log in tough for fear i would break our chareditlite modified characters. This start seems to fix the problematic data.
4-Stopped the server.
5- Resubscribed to CharEditLite.
6-Started the server.
7- Logged in normally, everything seems right, even the thralls and my character modified with CharEditLite, such as the half ogre Skallagrim, who is half again as big as normal chars:).
Maybe it can help somebody, cheers:)