Assertion Failed error garry's mod server

i launch start.bat and console error :
Console initialized.
ConVarRef mat_dxlevel doesn’t point to an existing ConVar
Game.dll loaded for “Garry’s Mod”
Initializing Steam libraries for Workshop…
steamengine.cpp (2345) : Assertion Failed: pBaseUser
Assert( Assertion Failed: pBaseUser ):steamengine.cpp:2345

help

[editline]3rd July 2016[/editline]

help

HELP PLEASE

Does the server crash after that?

i starting start.bat, not crash

Then what’s the issue if it’s not crashing?

http://i.hizliresim.com/bbRyDb.png

So it does crash

YEAH I NEED HELP HOW CAN I SOLVE PROBLEM

help

Help me please help

HELP PLS

HELP PLSSSSSSSSS