9735.309 Error MainLoop.cpp:1288: Exception at tick 747589199: The mod Drop Science Pack with Chest (4.0.0) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event DropSciencePack::on_research_finished (ID 18)
__DropSciencePack__/control.lua:476: attempt to index upvalue 'force_techs' (a nil value)
stack traceback:
    __DropSciencePack__/control.lua:476: in function <__DropSciencePack__/control.lua:473>

Screenshot: https://www.dropbox.com/s/scapco4a0m1rka1/error%20-%20drop%20science%20pack%20with%20chest.PNG?dl=0

Can you give more details on what happened? I tested all day and had no problems

I just had this occur a second time. The error occurs when research completes (in both cases, mining productivity 245). The first time, my game was idle, the second, I was doing construction via the map.

Modlist:

base
aai-loaders
aai-programmable-structures
aai-programmable-vehicles
aai-pv-crafting-group
aai-signals
aai-zones
Aircraft
alien-biomes
alien-biomes-hr-terrain
AlienSpaceScience
angelsaddons-storage
ArmouredBiters
belt-visualizer
BigLightElectricMiningDrill
bobenemies
boblibrary
Bottleneck
bullet-trails
chemical-rocket
circuit-poles
CircuitHUD-V2
CleanTiles
Constructron-Continued
dbots-artillery-bombardment-remote
Delete-Chunk-Tool
DropSciencePack
factoriohd_base
factoriohd_logistics
factoriohd_military
factoriohd_modpack
factoriohd_production
factoriohd_terrain
far-reach
FilterChests
flib
flip-dots
holographic_signs
Honk
informatron
jetpack
k2-flare-stack
lightorio
LoaderRedux
logistics_requests_sorted
mining-patch-planner
More_Bot_Health
nicefill
nonukescorch
nuclear_train
PickerDollies
PipeVisualizer
pollution-scaling
Power Armor MK3
power-grid-comb
puppy-jetpack-ui
Purple_Acid_Rain
pushbutton
regenerate-terrain
remove-nuclear-marks
reverse-factory
rs-base-scanner
scootys-armor-swap
Shield-FX-Updated
show-max-underground-distance
simhelper
simple_landfill_mining
some-spidertron
Sort-All-Inventories
space-spidertron
spidertron-dock
spidertron-extended
SpidertronEnhancements
Squeak Through
stdlib
TaskList
TrainRefuelStation
tree_collision
UnitLocationHotkeys
vehicle-physics
VehicleSnap
VilsClearNightvision
Waterfill_v17
WaterWell

can you share the save?

The crash occurs within a minute of this autosave (sorry about the size of the map + modlist). Thank you for looking in to this!

Hi, i'm writing now because i've been testing. I had no error, the game was on all night and in the morning it was still working. I did it because on your map I unfortunately have 10-15 fps :(

Error while running event DropSciencePack::on_research_finished (ID 18)
DropSciencePack/control.lua:476: attempt to index upvalue 'force_techs' (a nil value)
stack traceback:
DropSciencePack/control.lua:476: in function <DropSciencePack/control.lua:473>

https://drive.google.com/file/d/1jWAyRpwaPAfP5q_p3ftkrekGzYkZM5Tr/view?usp=sharing

This is save

Unfortunately, I can't test it on an experimental version. I lost access to all my schematics when I changed to stable version. If you had no problems with the previous version of the my mod, plz change it to an older one, if you are no using K2 or SE mods.

I got the schematics back but it was a bit of work

the mod is still ckrashed

https://drive.google.com/file/d/1jWAyRpwaPAfP5q_p3ftkrekGzYkZM5Tr/view?usp=sharing

This is save

I loaded the save, went to kill biters, ran it for 5 minutes with active research, and no crash happened. I am running the official version of Drop Science Pack 4.0.0

NOTE TO ALL:

If you want this bug addressed you must provide a savegame that uses the latest official version of Drop Science Pack and provide explicit step-by-step instructions starting from loading the save game.

maybe that helps i have the same issue and the problem arrises each time i load a save file with this mod. i deactivated every mod but this one.
if i activate or deactivate another mod before loading the save and just press Load instead of sync and Load. could it be that the array with the force values is not saved between saves?

and forcing the data to change with the activation or deactivation of another mod fills that array?

here is the error notice.
The mod Drop Science Pack with Chest (4.0.0) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event DropSciencePack::on_research_finished (ID 18)
DropSciencePack/control.lua:476: attempt to index upvalue 'force_techs' (a nil value)
stack traceback:
DropSciencePack/control.lua:476: in function <DropSciencePack/control.lua:473>

I know why this error occurred. You should make "force_techs" global value. But now this local value, when load the saves, this value will be nil.

same error！！！

you got it! :)