Can't Connect to any server

[Jenus358]

When a friend tries to connect to my server or to any other, it won't work and it puts out this log:
(He doesn't have any mods installed and it is no specific save game)

0.052 2017-09-15 17:36:50; Factorio 0.15.34 (build 30875, win64, steam)
0.052 Operating system: Windows 7 Service Pack 1
0.052 Program arguments: "C:\Program Files (x86)\Steam\steamapps\common\Factorio\bin\x64\Factorio.exe"
0.052 Read data path: C:/Program Files (x86)/Steam/steamapps/common/Factorio/data
0.052 Write data path: C:/Users/Marcel/AppData/Roaming/Factorio
0.052 Binaries path: C:/Program Files (x86)/Steam/steamapps/common/Factorio/bin
0.083 System info: [CPU: Intel(R) Celeron(R) 2955U @ 1.40GHz, 2 cores, RAM: 3980MB]
0.083 Display options: [FullScreen: 1] [VSync: 0] [UIScale: 100%] [MultiSampling: OFF] [Screen: 255] [Lang: de]
0.087 Available display adapters: 2
0.087 [0]: \\.\DISPLAY1 - Intel(R) HD Graphics {0x01, [1920,0], 1366x768, 32bit, 60Hz}
0.088 [1]: \\.\DISPLAY2 - Intel(R) HD Graphics {0x05, [0,0], 1920x1080, 32bit, 60Hz}
0.088 Create display on adapter 1. Size 1280x718 at position [310, 163].
0.286 Initialised Direct3D:[0] Intel(R) HD Graphics; driver: igdumdim64.dll 9.18.10.3234
0.323 Video memory size (dedicated video/dedicated system/shared system/available): 64/0/1632/1688 MB
0.432 DSound: Starting _dsound_update thread
0.433 Device reset internal.
0.433
0.441 Desktop composition is active.
0.441 Graphics settings preset: medium
0.442 Graphics options: [Graphics quality: normal] [Video memory usage: high] [Light scale: 25%] [DXT: false] [Shader: 1]
0.821 Loading mod core 0.0.0 (data.lua)
0.847 Loading mod base 0.15.34 (data.lua)
1.113 Loading mod base 0.15.34 (data-updates.lua)
1.197 Checksum for core: 1519575497
1.197 Checksum of base: 1503927233
1.976 Info PlayerData.cpp:60: Local player-data.json unavailable
1.976 Info PlayerData.cpp:63: Cloud player-data.json available, timestamp 1494174417
2.529 Loaded shader file C:/Program Files (x86)/Steam/steamapps/common/Factorio/data/core/graphics/shaders/game.cso
2.531 Loaded shader file C:/Program Files (x86)/Steam/steamapps/common/Factorio/data/core/graphics/shaders/zoom-to-world.cso
2.582 Initial atlas bitmap size is 8192
2.616 Created atlas bitmap 8192x8187
2.617 Created atlas bitmap 8192x1682
2.617 Created atlas bitmap 8192x2034
2.618 Created atlas bitmap 8192x1443
2.618 Created atlas bitmap 4096x3648
2.618 Created atlas bitmap 4096x1568
2.618 Created atlas bitmap 4096x1868
35.798 Sprites loaded
35.798 Convert atlas 4096x3648 to: mipmap
36.492 Convert atlas 4096x1568 to: mipmap
36.912 Convert atlas 4096x1868 to: trilinear-filtering
39.060 Loading sounds...
53.474 Custom inputs active: 0
53.717 Factorio initialised
230.477 Info UDPSocket.cpp:27: Opening socket at (0.0.0.0:0)
Factorio crashed. Generating symbolized stacktrace, please wait ...
c:\cygwin64\tmp\factorio-ymlunc\libraries\stackwalker\stackwalker.cpp (923): StackWalker::ShowCallstack
c:\cygwin64\tmp\factorio-ymlunc\src\util\logger.cpp (381): Logger::writeStacktrace
c:\cygwin64\tmp\factorio-ymlunc\src\util\logger.cpp (438): Logger::logStacktrace
c:\cygwin64\tmp\factorio-ymlunc\src\util\crashhandler.cpp (122): CrashHandler::writeStackTrace
c:\cygwin64\tmp\factorio-ymlunc\src\util\crashhandler.cpp (386): CrashHandler::SignalHandler
d:\th\minkernel\crts\ucrt\src\appcrt\misc\signal.cpp (516): raise
d:\th\minkernel\crts\ucrt\src\appcrt\startup\abort.cpp (71): abort
d:\th\minkernel\crts\ucrt\src\appcrt\misc\terminate.cpp (58): terminate
f:\dd\vctools\crt\vcruntime\src\eh\frame.cpp (762): FindHandler
f:\dd\vctools\crt\vcruntime\src\eh\frame.cpp (449): __InternalCxxFrameHandler
f:\dd\vctools\crt\vcruntime\src\eh\amd64\trnsctrl.cpp (186): __CxxFrameHandler3
ERROR: SymGetLineFromAddr64, GetLastError: 487 (Address: 000000007773812D)
000000007773812D (ntdll): (filename not available): RtlDecodePointer
ERROR: SymGetLineFromAddr64, GetLastError: 487 (Address: 000000007772855F)
000000007772855F (ntdll): (filename not available): RtlUnwindEx
ERROR: SymGetLineFromAddr64, GetLastError: 487 (Address: 0000000077728B58)
0000000077728B58 (ntdll): (filename not available): RtlRaiseException
ERROR: SymGetLineFromAddr64, GetLastError: 487 (Address: 000007FEFD69A06D)
000007FEFD69A06D (KERNELBASE): (filename not available): RaiseException
f:\dd\vctools\crt\vcruntime\src\eh\throw.cpp (136): _CxxThrowException
c:\cygwin64\tmp\factorio-ymlunc\src\net\udpsocket.cpp (406): UDPSocket::recvfrom
c:\cygwin64\tmp\factorio-ymlunc\src\net\pinger.cpp (39): Pinger::listen
c:\program files (x86)\microsoft visual studio 14.0\vc\include\thr\xthread (247): std::_LaunchPad<std::unique_ptr<std::tuple<std::_Binder<std::_Unforced,void (_cdecl Pinger::*)(void) _ptr64,Pinger _ptr64 const> >,std::default_delete<std::tuple<std::_Binder<std::_Unforced,void (_cdecl Pinger::*)(void) __ptr64,Pinger __ptr64 const> > > > >::_Run
c:\program files (x86)\microsoft visual studio 14.0\vc\include\thr\xthread (210): std::_Pad::_Call_func
d:\th\minkernel\crts\ucrt\src\appcrt\startup\thread.cpp (115): thread_start<unsigned int (_cdecl*)(void * _ptr64)>
ERROR: SymGetLineFromAddr64, GetLastError: 487 (Address: 00000000775059CD)
00000000775059CD (kernel32): (filename not available): BaseThreadInitThunk
ERROR: SymGetLineFromAddr64, GetLastError: 487 (Address: 000000007773A561)
000000007773A561 (ntdll): (filename not available): RtlUserThreadStart
261.030 Error Util.cpp:80: Unexpected error occurred. If you're running the latest version of the game you can help us solve the problem by posting the contents of the log file on the Factorio forums.
Please also include the save file(s), any mods you may be using, and any steps you know of to reproduce the crash.

[Loewchen]

52290

[Jenus358]

Thanks! It works now!