Hope you can help guys! it’s a weird one, its my Lvl7 that’s the problem. to a starter i got the EXCEPTION_ACCESS_VIOLATION, i then loaded a previews version of the umap, that worked and it loaded the lvl successful. i can work within the lvl but when i try to safe it, i cant re open the lvl within the project again. I get the same result again, i then did the umap replacement again, and it opens op again! cool! Then i tried to just copy a single rock within the lvl and saved it. closed the project and now the problem accurse again!!! What’s going on here XD ?
is this a purely Blueprint project or is there C++ included?
does this happen with other levels in your project?
you state this is Lvl7, so what is different between Lvl7 and for example 6? is a new mechanic introduced, or a new object type? you will probably be focusing on these.
EXCEPTION_ACCESS_VIOLATION means that when there is an attempt to access a pointer without it being tested for validity first, it was pointing to NULL (had not been fully initialized), or it was removed by Garbage Collection (often times this has to do with how the pointer is defined)
Does it crash immediately when the map opens? after a few moments? when you are able to open the map, can you get into PIE? does it run in PIE without doing anything for more then like 5 or 10 minutes?
look at your output logs. outside of extreme cases the engine will include a stack trace on exception “`[projectName]/Saved/Logs/`" the most recent will be the one at the top, all the other ones will have UTC time codes.
if you have the engine symbols generated or installed with the engine then the full stack trace will be there, if you don’t have the symbols; things get harder without them.
the biggest culprit will be pointers (blueprint references) that are being accessed without a check for IsValid()first (in blueprints this is a specific node the one with the “?” has exec pins instead of needing to feed into a boolean branch)
Thanks for the quick answer! It only happens with the Lvl7 inside my project i do have a ton of references in lvl7 compared to the others, and i did not use the IsValid. I will try to load in the older umap again and then go throe all the blueprints, and yes it is all blueprints in my project. I’m new to developing, have done this for 6 months and I’m currently about to release my game, if i can get this one fixed how ever..
the “good” news is to check this you don’t need to specifically open the map to look at the blueprints, the blueprint scripts can be access through the content panel (the hardest part is figuring out what was used)
and it might just be that your other levels were not complex enough to hit this issue, but your level 7 just so happen to miss one assignment in the Details Panel, leading to your ACCESS_VIOLATION being thrown.
if your blueprints are rather complex, right click on your pointers (Blueprint References) in the Variables section of the Blueprint and select “Find All References” this will give you a list of each time each of those things was used in that given Blueprint class. and just be sure that right before he first time it is accessed put it into an IsValid() I would suggest that out of the fail state of the IsValid() putting a print string on what to fix (these will be removed for release, or have some way to try and acquire what is needed but this can get very advanced or specific)
- you will also need to look at each time a pointer is passed into a function/Event and before it is used to do the same.
for things being accessed in a DelayLoop, or Tick() check these in BeginPlay() instead, or right before the DelayLoop, unless there is some chance the thing could disappear between Tick() cycles, or while the DelayLoop is ticking then take the hit on the processor cycles and check in the middle of Tick or the DelayLoop. Anything else might require rethinking your design to a lot lower level.
This seams like a daunting thing and maybe a little bit overboard, but at least you caught it now, before release, and not having to respond to people posting about how your game is broken, and in some instances crashing their entire computer because you missed a safety node. 
I went throe all of the blueprints now and added isvalid where needed, it did not help ? The problem for me started when i tried to change the LOD settings on my tree mesh that i use for foliage that’s actually where i got my first crash i deleted the foliage and the assets! That did not work as well. Funny thing is that at the same time i started to get Status Access Violation in my browser as well ? youtube, netflix and hbo crashes all the time and i need to do a refresh. it happens 50 times doing a movie! maybe its connected ? actually i get the error sometimes when i just try to load up my project. Something wrong with my hardware maybe ?
can you list your PC specs specifically your CPU, GPU (I am suspecting the CPU more then the GPU though), Motherboard full name, OS drive type (NvMe SSD, or SATA drive)
is it just an Access Violation, or do you also get things about ‘Out of video memory’?
does the system when under load just suddenly hard-lock/crash (requiring the system to be rebooted manually), or reboot itself?
did this start after like an OS update? or a Hardware upgrade?