Steam Updated, Now Game Won't Load

[firstmistakelastmistake]

Hi.  Thought I'd ask here because this forum seems to be extremely knowledgeable.  Played for a few hours yesterday (60hrs total so far), but after a Steam update now nothing will load.  

I have been launching through fnv4gb.exe for a while.  However now that gives me an "Original exe modified -> Executable headers failed to validate.  An unmodified original exe is required.  You should get steam to validate your game cache and download unmodified versions of any files."

If I go to FOMM and launch NVSE, I get an error that Launching FalloutNV.exe failed (740).  

If I launch from Steam I get "Application load error 3:0000065432".

I assume that the Steam update changed some file or permissioning, but what?  I turned off read only on fallout.ini and set falloutnv.exe to "run as admin". 

Thanks for your help.

PC: i5-4670K 3.4ghz/8gb ram/x64

Load order:

FalloutNV.esm DeadMoney.esm HonestHearts.esm OldWorldBlues.esm LonesomeRoad.esm GunRunnersArsenal.esm CaravanPack.esm ClassicPack.esm MercenaryPack.esm TribalPack.esm Fallout3.esm Anchorage.esm ThePitt.esm BrokenSteel.esm PointLookout.esm Zeta.esm TaleOfTwoWastelands.esm Project Nevada - Core.esm Project Nevada - Equipment.esm Project Nevada - Rebalance.esp Project Nevada - Cyberware.esp Project Nevada - Extra Options.esm StreetLights.esm TTWInteriors_Core.esm TTWInteriorsProject_Combo.esm TTWInt_FollowerGoHome.esm ttw_wildwasteland.esp TTWOptions.esp TTW_StashPackOptions.esp TTW_StartupMenu.esp TTW_SpeechChecks.esp TTW_OutcastTrading.esp TTW_Reputation.esp TTW_AnchorageCustomization.esp Project Nevada - TTW.esp Project Nevada - Cyberware Additions.esp Project Nevada - Rebalance Complete.esp Project Nevada - All DLC.esp The Mod Configuration Menu.esp TTW_XPReduction.esp TTWIntMojaveExpressBoxes_Combo.esp ttw_speedtreefix_1.esp   Total active plugins: 42 Total plugins: 42  

[rbroab]

This same issue happened to me about a month ago when my Steam updated. For me, the fix was to restart Steam. Other than that, if you google the issue, some people have reported that deleting a certain file makes the game work again. Can't remember the name off the top of my head, and I'm posting from a phone or I'd google it for you. But it should come up if you google the error you're getting. 

[mayoko]

http://forum.hiddenpath.com/forum/hidden-path-forums/defense-grid-technical-support/396-error-51-on-steam-solution?376-Error-51-on-Steam-solution=

Try deleting the clientregistry.blob and check your firewall to make sure steam is allowed, if that doesn't work, copy the steam.dll from your steam program folder and rename the original in the fnv folder, paste the new one. (this was an issue with Plants Vs Zombies when I was using steam beta and after an update nothing could make it run)

Also if those don't work you should definately verify FNV game files through steam.

Another thing you could try is updating your graphics card driver or using the last iteration if it recently updated.

[RoyBatty]

If you use FNV4GB, and you started it without steam running it can cause this problem.

Go into the root Fallout New Vegas directory, and delete the "exes" folder. If you use the launch options, then delete FalloutNV4GB.exe

exit and restart steam.

[firstmistakelastmistake]

I tried roybatty's solution first because I thought it looked the simplest & therefore a good place to start.

I deleted the "exes" folder, even though it looked like it was empty.  Then I launched, thinking "there's no way this will work, all I did was delete an empty directory".  

Well it worked.  Wow.  Are you a wizard?