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error LNK2019 unresolved external symbol from fltlib.lib

amirdamird Member Posts: 1

I got some c++ project (VS 2019) that I need to work on.
the problem is when compiling the project I get 2 errors:

LNK2019 unresolved external symbol FilterConnectCommunicationPort
LNK2019 unresolved external symbol FilterSendMessage

from what I read those functions are from the fltlib dll and I need to include the fltlib.lib in my project

I did manage to download the fltlib.dll but i don't know how to get the lib file (my project already has the header file needed)

  1. Where can I get the lib file?
  2. how to link it in my project?

I'm not a c++ developer so if this is a trivial question my apologies



  • rod_widdowsonrod_widdowson Member - All Emails Posts: 1,266

    I'm pretty sure it comes down with the WDK (although I guess it might be the SDK). For me, it's here

    Directory of C:\Program Files (x86)\Windows Kits\10\Lib\10.0.22000.0\um\x64
    04/06/2021  17:07             8,302 fltLib.lib
  • HHosseinKHHosseinK Member Posts: 8

    Hi, Please Download and Install WDK and then get this lib from within the WDK installed path and add to the Visual Studio Linker path :

    Project -> Properties -> Linker -> Input -> ( Add fltlib.lib )

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