Installing on Mint 18.1

I’m trying to install the latest version of Unreal Engine onto my HP Probook 4540s running Mint 18.1. After i start Setup.sh, I get this message and setup stops:
The following NEW packages will be installed:
clang-3.9 gcc-4.9-base libasan1 libclang-common-3.9-dev libclang1-3.9
libgcc-4.9-dev libllvm3.9 libobjc-4.9-dev libstdc+±4.9-dev
0 upgraded, 9 newly installed, 0 to remove and 38 not upgraded.
Need to get 89.0 MB of archives.
After this operation, 258 MB of additional disk space will be used.
WARNING: The following packages cannot be authenticated!
libllvm3.9 libclang1-3.9 libclang-common-3.9-dev clang-3.9
E: There were unauthenticated packages and -y was used without --allow-unauthenticated

Can you help me, please?

Looks like Mint hasn’t upgraded the security certificates again. Just manually install the packages with

sudo apt-get install -y --allow-unauthenticated clang-3.9 gcc-4.9-base libasan1 libclang-common-3.9-dev libclang1-3.9 libgcc-4.9-dev libllvm3.9 libobjc-4.9-dev libstdc++-4.9-dev

Then rerun the script

Looks like that worked. Thanks!

Any Time (: