Problem when building on Ubuntu

Sorry to disturb you guys. I was building Unreal Engine 4.26 on Ubuntu 20.04 LTS. I ran the ./ and the ./ properly, and they all seem to ran succeessfully. However, I got the error message below:

cjc@cjc-Lenovo-Rescuer-15ISK:~/UnrealEngine$ make
bash "/home/cjc/UnrealEngine-1/Engine/Build/BatchFiles/Linux/" CrashReportClient Linux Shipping  
Fixing inconsistent case in filenames.
Setting up Mono
Running command : Engine/Binaries/DotNET/UnrealBuildTool.exe CrashReportClient Linux Shipping
Using 'git status' to determine working set for adaptive non-unity build (/home/cjc/UnrealEngine-1).
Creating makefile for CrashReportClient (no existing makefile)
ERROR: Platform Linux is not a valid platform to build. Check that the SDK is installed properly.
make: *** [Makefile:327:CrashReportClient-Linux-Shipping] 错误 6

How to solve it?
My CPU: Intel i7-6700HQ@2.6GHz
My GPU:Nvidia GTX 960M
By the way, is it common that no third-party toolchain needs to be build when running ./ for the first time? I consider it to be abnormal because GFW often blocks someting with no reason.

Remove the contents of Engine/Extras/ThirdPartyNotUE/SDKs/HostLinux/Linux_x64 and re-run the commands starting with

This is on Ubuntu 20.04.3 LTS in a git checkout that previously built 4.26 and I wanted a 4.27 preview which was using different clang libs. I think it was confused by multiple libs being at that location.

Thanks bro. However, my solution is download something manually instead of using, and then execute again :slight_smile: