I need how to solve ‘session server is not found’.
Please give more details on your issue specially which OS are you using?
Firewall may be preventing access?
I installed salome9.8 in Ubuntu20.04 and now it looks like this after I removed salome9.8.
Assuming that you want to run SALOME 9.12 as shown in the splash screen capture, you need to ensure that system prerequisites are present by running:
sat/sat config SALOME-9.12.0-native --check_system
If it does not help, then share the output of :
apt list --installed
command line.
Note that you can still use the universal binary which embeds all required system packages.