Version `GLIBC_2.35' not found

After installing fluka and flair, when opening flair there are shown such error:

w> Warning: Geometry Viewer not found
e> ERROR: /lib/x86_64-linux-gnu/ version `GLIBC_2.35’ not found (required by /usr/local/flair/

What’s the problem and what to do ?

Dear @sergey.a,

Did you try upgrading libc6 package?


sudo apt-get update
sudo apt-get install libc6


I did as you say. But it shows that there are installed version 2.31. How install 2.35 version ?

Dear Sergey,

please check if you are trying to install the correct package version for your system.

Based on the glibc version numbers, I’m guessing that are trying to install the package intended for Ubuntu 22.04 on a Ubuntu 20.04 system.