https://hardcore-games.azurewebsites.net/wp/win/it/fix-steam-games.php
I did even more tough cleanup, even redownloaded whole game, clean install, but it just doesnt want to work anymore, unless I renable fastprox.dll in systemwow64/webm folder
https://support.steampowered.com/kb\_article.php?ref=3134-TIAL-4638
https://support.steampowered.com/kb\_article.php?ref=2037-QEUH-3335
https://support.steampowered.com/kb\_article.php?ref=4168-TLZB-4976&l=english
Im re-verying again, will try 2x now...
this is the error in detail
Version=1
EventType=APPCRASH
EventTime=130890853557883311
ReportType=2
Consent=1
UploadTime=130890880096232646
ReportIdentifier=ec43e3f6-707c-11e5-8cca-74d02b2b2df8
IntegratorReportIdentifier=a8ef7ae7-0a90-4d06-bdb2-b0561f1589f3
WOW64=1
NsAppName=left4dead2.exe
Response.type=4
Sig[0].Name=Application Name
Sig[0].Value=left4dead2.exe
Sig[1].Name=Application Version
Sig[1].Value=0.0.0.0
Sig[2].Name=Application Timestamp
Sig[2].Value=545ac24d
Sig[3].Name=Fault Module Name
Sig[3].Value=shaderapidx9.dll
Sig[4].Name=Fault Module Version
Sig[4].Value=0.0.0.0
Sig[5].Name=Fault Module Timestamp
Sig[5].Value=55f9b421
Sig[6].Name=Exception Code
Sig[6].Value=c0000005
Sig[7].Name=Exception Offset
Sig[7].Value=00036606
DynamicSig[1].Name=OS Version
DynamicSig[1].Value=10.0.10240.2.0.0.256.48
DynamicSig[2].Name=Locale ID
DynamicSig[2].Value=1060
DynamicSig[22].Name=Additional Information 1
DynamicSig[22].Value=bdcb
DynamicSig[23].Name=Additional Information 2
DynamicSig[23].Value=bdcb33e65a9843796b7ec31cc25bda3b
DynamicSig[24].Name=Additional Information 3
DynamicSig[24].Value=689d
DynamicSig[25].Name=Additional Information 4
DynamicSig[25].Value=689d12abf00dd47c453b5e1a156c0fa3
UI[2]=D:\Steam\steamapps\common\Left 4 Dead 2\left4dead2.exe
UI[3]=left4dead2.exe has stopped working
UI[4]=Windows can check online for a solution to the problem.
UI[5]=Check online for a solution and close the program
UI[6]=Check online for a solution later and close the program
UI[7]=Close the program
LoadedModule[0]=D:\Steam\steamapps\common\Left 4 Dead 2\left4dead2.exe
LoadedModule[1]=C:\WINDOWS\SYSTEM32\ntdll.dll
LoadedModule[2]=C:\WINDOWS\SYSTEM32\KERNEL32.DLL
LoadedModule[3]=C:\WINDOWS\SYSTEM32\KERNELBASE.dll
LoadedModule[4]=C:\WINDOWS\system32\apphelp.dll
LoadedModule[5]=C:\WINDOWS\SYSTEM32\USER32.dll
LoadedModule[6]=C:\WINDOWS\SYSTEM32\GDI32.dll
LoadedModule[7]=C:\WINDOWS\SYSTEM32\IMM32.DLL
LoadedModule[8]=C:\WINDOWS\SYSTEM32\MSCTF.dll
LoadedModule[9]=C:\WINDOWS\SYSTEM32\msvcrt.dll
LoadedModule[10]=D:\Steam\gameoverlayrenderer.dll
LoadedModule[11]=C:\WINDOWS\SYSTEM32\ADVAPI32.dll
LoadedModule[12]=C:\WINDOWS\SYSTEM32\sechost.dll
LoadedModule[13]=C:\WINDOWS\SYSTEM32\RPCRT4.dll
LoadedModule[14]=C:\WINDOWS\SYSTEM32\WINMM.dll
LoadedModule[15]=C:\WINDOWS\SYSTEM32\SspiCli.dll
LoadedModule[16]=C:\WINDOWS\SYSTEM32\CRYPTBASE.dll
LoadedModule[17]=C:\WINDOWS\SYSTEM32\bcryptPrimitives.dll
LoadedModule[18]=C:\WINDOWS\SYSTEM32\ole32.dll
LoadedModule[19]=C:\WINDOWS\SYSTEM32\combase.dll
LoadedModule[20]=C:\WINDOWS\SYSTEM32\WINMMBASE.dll
LoadedModule[21]=C:\WINDOWS\SYSTEM32\cfgmgr32.dll
LoadedModule[22]=C:\WINDOWS\SYSTEM32\DEVOBJ.dll
LoadedModule[23]=C:\WINDOWS\SYSTEM32\psapi.dll
LoadedModule[24]=D:\Steam\steamapps\common\Left 4 Dead 2\bin\launcher.dll
LoadedModule[25]=C:\WINDOWS\SYSTEM32\SHELL32.dll
LoadedModule[26]=C:\WINDOWS\SYSTEM32\windows.storage.dll
LoadedModule[27]=C:\WINDOWS\SYSTEM32\shlwapi.dll
LoadedModule[28]=C:\WINDOWS\SYSTEM32\kernel.appcore.dll
LoadedModule[29]=C:\WINDOWS\SYSTEM32\shcore.dll
LoadedModule[30]=C:\WINDOWS\SYSTEM32\powrprof.dll
LoadedModule[31]=C:\WINDOWS\SYSTEM32\profapi.dll
LoadedModule[32]=D:\Steam\steamapps\common\Left 4 Dead 2\bin\steam_api.dll
LoadedModule[33]=C:\WINDOWS\SYSTEM32\WSOCK32.dll
LoadedModule[34]=D:\Steam\steamapps\common\Left 4 Dead 2\bin\tier0.dll
LoadedModule[35]=D:\Steam\steamapps\common\Left 4 Dead 2\bin\vstdlib.dll
LoadedModule[36]=C:\WINDOWS\SYSTEM32\WS2_32.dll
LoadedModule[37]=C:\WINDOWS\SYSTEM32\NSI.dll
LoadedModule[38]=D:\Steam\steamapps\common\Left 4 Dead 2\bin\filesystem_stdio.dll
LoadedModule[39]=C:\WINDOWS\system32\uxtheme.dll
LoadedModule[40]=d:\steam\steamapps\common\left 4 dead 2\bin\engine.dll
LoadedModule[41]=C:\WINDOWS\SYSTEM32\WININET.dll
LoadedModule[42]=C:\WINDOWS\SYSTEM32\IPHLPAPI.DLL
LoadedModule[43]=C:\WINDOWS\SYSTEM32\WINNSI.DLL
LoadedModule[44]=d:\steam\steamapps\common\left 4 dead 2\bin\inputsystem.dll
LoadedModule[45]=d:\steam\steamapps\common\left 4 dead 2\bin\materialsystem.dll
LoadedModule[46]=d:\steam\steamapps\common\left 4 dead 2\bin\datacache.dll
LoadedModule[47]=d:\steam\steamapps\common\left 4 dead 2\bin\studiorender.dll
LoadedModule[48]=d:\steam\steamapps\common\left 4 dead 2\bin\vphysics.dll
LoadedModule[49]=d:\steam\steamapps\common\left 4 dead 2\bin\vscript.dll
LoadedModule[50]=d:\steam\steamapps\common\left 4 dead 2\bin\valve_avi.dll
LoadedModule[51]=d:\steam\steamapps\common\left 4 dead 2\bin\binkw32.dll
LoadedModule[52]=C:\WINDOWS\SYSTEM32\AVIFIL32.dll
LoadedModule[53]=C:\WINDOWS\SYSTEM32\MSVFW32.dll
LoadedModule[54]=C:\WINDOWS\SYSTEM32\MSACM32.dll
LoadedModule[55]=C:\WINDOWS\WinSxS\x86_microsoft.windows.common-controls_6595b64144ccf1df_5.82.10240.16384_none_49c02355cf03478c\COMCTL32.dll
LoadedModule[56]=d:\steam\steamapps\common\left 4 dead 2\bin\vguimatsurface.dll
LoadedModule[57]=d:\steam\steamapps\common\left 4 dead 2\bin\vgui2.dll
LoadedModule[58]=D:\Steam\steamapps\common\Left 4 Dead 2\bin\shaderapidx9.dll
LoadedModule[59]=C:\WINDOWS\SYSTEM32\OLEAUT32.dll
LoadedModule[60]=d:\steam\steamapps\common\left 4 dead 2\d3d9.dll
LoadedModule[61]=C:\WINDOWS\SYSTEM32\MSVCP110.dll
LoadedModule[62]=C:\WINDOWS\SYSTEM32\MSVCR110.dll
LoadedModule[63]=C:\WINDOWS\system32\d3d9.dll
LoadedModule[64]=C:\WINDOWS\SYSTEM32\dwmapi.dll
LoadedModule[65]=C:\WINDOWS\SYSTEM32\nvd3dum.dll
LoadedModule[66]=C:\WINDOWS\SYSTEM32\VERSION.dll
LoadedModule[67]=D:\Steam\steamclient.dll
LoadedModule[68]=C:\WINDOWS\SYSTEM32\CRYPT32.dll
LoadedModule[69]=C:\WINDOWS\SYSTEM32\MSASN1.dll
LoadedModule[70]=C:\WINDOWS\SYSTEM32\imagehlp.dll
LoadedModule[71]=C:\WINDOWS\SYSTEM32\SETUPAPI.dll
LoadedModule[72]=D:\Steam\vstdlib_s.dll
LoadedModule[73]=D:\Steam\tier0_s.dll
LoadedModule[74]=C:\WINDOWS\SYSTEM32\Secur32.dll
LoadedModule[75]=D:\Steam\crashhandler.dll
LoadedModule[76]=D:\Steam\steamapps\common\Left 4 Dead 2\bin\XInput1_3.dll
LoadedModule[77]=C:\WINDOWS\SYSTEM32\WINTRUST.dll
LoadedModule[78]=C:\WINDOWS\SYSTEM32\DINPUT.DLL
LoadedModule[79]=C:\WINDOWS\SYSTEM32\HID.DLL
LoadedModule[80]=d:\steam\steamapps\common\left 4 dead 2\bin\stdshader_dbg.dll
LoadedModule[81]=d:\steam\steamapps\common\left 4 dead 2\bin\stdshader_dx9.dll
LoadedModule[82]=d:\steam\steamapps\common\left 4 dead 2\bin\chromehtml.dll
LoadedModule[83]=d:\steam\steamapps\common\left 4 dead 2\bin\libcef.dll
LoadedModule[84]=C:\WINDOWS\SYSTEM32\COMDLG32.dll
LoadedModule[85]=C:\WINDOWS\SYSTEM32\USP10.dll
LoadedModule[86]=C:\WINDOWS\SYSTEM32\WINSPOOL.DRV
LoadedModule[87]=C:\WINDOWS\SYSTEM32\WINHTTP.dll
LoadedModule[88]=C:\WINDOWS\SYSTEM32\USERENV.dll
LoadedModule[89]=C:\WINDOWS\SYSTEM32\urlmon.dll
LoadedModule[90]=C:\WINDOWS\SYSTEM32\dhcpcsvc.DLL
LoadedModule[91]=C:\WINDOWS\SYSTEM32\MSIMG32.dll
LoadedModule[92]=C:\WINDOWS\SYSTEM32\bcrypt.dll
LoadedModule[93]=C:\WINDOWS\SYSTEM32\iertutil.dll
LoadedModule[94]=d:\steam\steamapps\common\left 4 dead 2\bin\icudt.dll
LoadedModule[95]=C:\WINDOWS\SYSTEM32\clbcatq.dll
LoadedModule[96]=C:\WINDOWS\SYSTEM32\wbem\wbemprox.dll
LoadedModule[97]=C:\WINDOWS\SYSTEM32\wbemcomn.dll
LoadedModule[98]=C:\WINDOWS\SYSTEM32\cryptsp.dll
LoadedModule[99]=C:\WINDOWS\system32\rsaenh.dll
LoadedModule[100]=C:\WINDOWS\SYSTEM32\wbem\wbemsvc.dll
LoadedModule[101]=C:\WINDOWS\SYSTEM32\wbem\fastprox.dll
FriendlyEventName=Stopped working
ConsentKey=APPCRASH
AppName=left4dead2.exe
AppPath=D:\Steam\steamapps\common\Left 4 Dead 2\left4dead2.exe
NsPartner=windows
NsGroup=windows8
ApplicationIdentity=3EF267D92DB197D4EE93CD7CE64BA99D
EDIT: nope, same issue persists.. :\