So yesterday I was playing the standalone totally fine. No errors, nothing to worry about. I noticed I've had an issue for a while with my Master Boot Record (100% unrelated to DayZ considering I didn't even start to play again within the past couple of days after a solid 6 month hiatus) and decided to fix it about yesterday afternoon. I popped my Win7 disc in, fixed the MBR, called it a day. Jump back into steam and try to run DayZ, now I'm getting one of two outcomes whenever I launch the game: 1. My game starts on a black screen, then crashes a few seconds later providing me with the error: "The instruction at 0x00000000 referenced memory at 0x00000000. The memory could not be written." Granted that's not the exact memory address listed in the error, but every time, both addresses end up being the exact same. OR 2. The game goes to a black screen and sits frozen for eternity (I let the black screen sit (without the error message popping up) for the entire night I slept last night and nothing changed). Solutions I have tried: Restart computer Restart Steam Reinstall DayZ onto new hard drive and original hard drive Verify Game Cache like 1,000,000 times Download BEClient.dll directly from the Battle Eye website Considering a complete re-install of Win7 is not in the cards for me because that would involve literally a day of re-configuring everything and reinstalling a lot of software, I'd really like to avoid that. Also I've done a memtest and memory seems solid. It is LITERALLY only DayZ standalone giving me this issue. I played the mod for a solid 4 hours straight without a hiccup. No other games are giving me this issue whatsoever. I've run every single one in my library and this is the only one that has not been able to run once since I fixed my MBR. Plzhelp thnx. Edit: System Specs just in case someone needs them- AMD 8350 (4ghz 8 core not overclocked) 1tb HDD (the other Hard Drive I tried installing it on is 500 GB USB 2 external, where the rest of my arma games are installed) 16gb DDR3 1600mhz GTX 780 3gb VRAM ASUS Sabertooth R2.0 Mobo Edit 2: I should probably mention that whenever I try to run the BattleEye service, the command prompt just blinks onto the screen and immediately disappears. No text is displayed or anything. Even if I run as Admin. Not sure what's up with that, heard it could be related potentially. Edit 3: When trying to run in compatibility (win xp sp 3) mode, the message "Unable to locate a running instance of Steam" is displayed and the game never runs. Both when I double click the exe directly or when I launch through steam, both give the same outcome. UPDATE: So I just went and flushed the configuration for Steam (steam://flushconfig). I restarted my computer, then ran Steam in Admin mode. Tried running DayZ a couple of times through Steam but given the same results. NOW I just tried running it by double-clicking the exe directly (while running in Compatibility Mode) and it made it to the page where you have to click "I understand" but then immediately crashed. Just before it got to the Bohemia Interactive screen, I noticed the error message "The instruction at 0x00000000 referenced memory at 0x00000000. The memory could not be written." came up but my game didn't crash until I hit the "I understand" page. Progress at least! Edit 4: So I just tried running it through steam and it gave the same exact result as above now. It keeps giving me the memory error. I'm so confused though considering it loads to that page and crashes, if there was really a memory issue I feel the game would keep crashing as it's been doing before. Edit 5: Okay so I double clicked on the DayZ exe and the DayZ_BE exe and both gave me the result of the game loading to a black screen and staying frozen again. I can tell that nothing's going on because my Resource Monitor shows me that every time the game starts and sits at that black screen, the process immediately stops using any CPU. As with the other situation (the memory error situation) the game does not respond for a brief few seconds but continues to use CPU and then loads the Bohemia Interactive screen and stops displaying as "Not Responding". What in the HELL is going on?? Edit 6: Ran compatibility with Vista Sp 2 and was given the memory error but it didn't even load to the Bohemia Interactive logo. Just went to the black screen, crashed and gave me the error. So far XP seems to be the one that gets me farthest. Edit 7: Two things: First, I tried running DayZ.exe directly and running it through Steam and for about 10 attempts straight I was granted with just freezing situations. About the 11th attempt I ran through Steam and got it to get back to the "I Understand" page. So at least it's a note of consistency that running in Compatibility mode in XP SP 2 gets me farther than anything else so far. Edit 8: Performed "sfc /scannow" and found corrupt files. None of which are related to DayZ. Nothing has changed for DayZ even after performing the scan. Edit 9: The following picture shows the errors I've gotten the last 4 times I've run the game and it made it to the "I Understand" page: http://imgur.com/iutcjvh Also, side-note, the middle two errors happen to have the same address. Those two instances were probably within 20-30 minutes of each other. I also witnessed an instance just before I started taking screenshots where that same memory address showed up in an error screen prior. Also the last 16-bits always end up being "a5e0" not sure if that's relative. Edit 10: I've now had three recorded instances of the same memory addresses that could not be written to in a row: 0x584ea5e0. I'm gonna pull my hair out by day's end I swear. Edit 11: So I just now tried to run it again. When I heard the error message pop up (just before the Bohemia Interactive logo appeared), I quickly went to the desktop and hit "Cancel" to attempt to debug myself. I opened a debug session in Visual Studio 2013 but the program was not able to be attached because access was denied. If I could just open the process myself I could figure out what's going on with the handling of memory blah. Edit 12: The complete and utter vanquishing of any trace of DayZ from my PC and then safely reinstalling it as if it were a fresh shiny brand new game did nothing. Still back to where we were before. I'm curious mostly because the error always displays the same two memory addresses. As in the first and second memory addresses reported in each error are the same (eg. The instruction at 0x584ea5e0 referenced memory at 0x584ea5e0). From my layman understanding of memory and instruction handling, trying to call memory in an instruction's own memory space is bounds for an infinite loop of instruction calling. Like an ouroboros. So either A. the instruction is not trying to access the right space of memory and keeps hitting itself each time, or B. there's an instruction being stored in a place where other memory should be held,

Gracias sir. I know it's a pretty widely known issue, it's affected more than just DayZ. I just find it very odd that DayZ is the only program this happens with in my situation. Not to mention that both memory address listed usually point to an issue with RAM but I'm not having any errors in memtest. I appreciate your help and yeah please let me know if anything develops.

Having the same issue except my memory addresses in the error are the same. I've made a thread https://forums.dayzgame.com/index.php?/topic/229295-very-strange-launching-situation/ <-here that completely and thoroughly details what I've done and what's been going on. So far I'm stuck without much progress beyond the fact that running it in compatibility mode with XP SP2 gets me to the "I Understand" page but then crashes immediately after. Even getting to that page is not guaranteed, considering most times I attempt to run it, it just freezes at a black screen anyway (but it doesn't print the error message at least when it does freeze).

*Update moved to OP for organization*

I haven't touched the registry yet considering I doubt memory address issues have anything to do with registry mismatching but I mean I'll give it a shot I guess. I'm just really totally at a loss here.