hello im getting this error unexpected error occured:
windowsbase 4.0.0.0 culture=neutral, publickeytoken=31bf3856ad364e35
and on my desktop i got Arma3Launcher_Exception_20180106T020235
and in it was

Arma 3 Launcher Exception Log

Arma 3 Launcher has encountered an unexpected error described below.
Sorry for the inconvenience.
Please report this on Arma 3 Feedback Tracker (http://feedback.arma3.com). Thanks to you we may fix the issue faster!

System information

Date: 2018-01-06 02:02:35 / 2018-01-06 03:02:35 +01
Current dir: C:\Program Files (x86)\Steam\steamapps\common\Arma 3
AppData dir: C:\Users\justi\AppData\Local
Command line: "C:\Program Files (x86)\Steam\steamapps\common\Arma 3\arma3launcher.exe"
Version: 1.5.143.751
CLR version: 4.0.30319.42000
OS Version: 10.0.15063.0 (Microsoft Windows NT 10.0.15063.0)
OS 64 bit: True
Process 64 bit: False
Personal dir: C:\Users\justi\Documents
Culture: nl-NL
UI Culture: nl-NL
Point of log: Unhandled Exception

Exception

System.IO.FileNotFoundException: Kan bestand of assembly WindowsBase, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35 of een van de afhankelijkheden hiervan niet laden. Het systeem kan het opgegeven bestand niet vinden.
Bestandsnaam: WindowsBase, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35

bij Launcher.Program.StartGui(InitArgs param)
bij Launcher.Program.HandleCommandLine()
bij Launcher.Program.RunLauncher()
bij Launcher.Program.Main(String[] args)

WRSCH: registratie van assembly-bindingen is uitgeschakeld.
Als u assembly-bindingsfouten wilt registreren, stelt u de registerwaarde [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) in op 1.
Opmerking: er is een prestatiestraf gekoppeld aan de registratie van assembly-bindingsfouten.
Als u deze functie wilt uitschakelen, verwijdert u de registerwaarde [HKLM\Software\Microsoft\Fusion!EnableLog].

Modules and assemblies

• mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089; C:\Windows\Microsoft.NET\Framework\v4.0.30319\mscorlib.dll
• arma3launcher, Version=1.5.143.751, Culture=neutral, PublicKeyToken=null; C:\Program Files (x86)\Steam\steamapps\common\Arma 3\arma3launcher.exe
• log4net, Version=1.2.13.0, Culture=neutral, PublicKeyToken=669e0ddf0bb1aa2a; C:\Program Files (x86)\Steam\steamapps\common\Arma 3\Launcher\log4net.dll
• System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089; C:\WINDOWS\Microsoft.Net\assembly\GAC_MSIL\System\v4.0_4.0.0.0__b77a5c561934e089\System.dll
• System.Configuration, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a; C:\WINDOWS\Microsoft.Net\assembly\GAC_MSIL\System.Configuration\v4.0_4.0.0.0__b03f5f7f11d50a3a\System.Configuration.dll
• System.Core, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089; C:\WINDOWS\Microsoft.Net\assembly\GAC_MSIL\System.Core\v4.0_4.0.0.0__b77a5c561934e089\System.Core.dll
• System.Xml, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089; C:\WINDOWS\Microsoft.Net\assembly\GAC_MSIL\System.Xml\v4.0_4.0.0.0__b77a5c561934e089\System.Xml.dll
• SharedResources, Version=1.5.143.751, Culture=neutral, PublicKeyToken=null; C:\Program Files (x86)\Steam\steamapps\common\Arma 3\Launcher\SharedResources.dll
• PresentationFramework, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35; C:\WINDOWS\Microsoft.Net\assembly\GAC_MSIL\PresentationFramework\v4.0_4.0.0.0__31bf3856ad364e35\PresentationFramework.dll
• mscorlib.resources, Version=4.0.0.0, Culture=nl, PublicKeyToken=b77a5c561934e089; C:\WINDOWS\Microsoft.Net\assembly\GAC_MSIL\mscorlib.resources\v4.0_4.0.0.0_nl_b77a5c561934e089\mscorlib.resources.dll

Assembly resolution

Resolving WindowsBase, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35

requested by: unknown
not resolved