Hi @VV86
If you need to use a proxy to access the internet, you can set that under File → Preferences → General → Network Connections by setting the Active Provider to Manual and configuring the Proxy entries.
If that doesn’t work you can also manually download and point KNIME Analytics Platform to local update sites: KNIME Analytics Platform Installation Guide
Kind regards
Marvin
EDIT: If you’re in a corporate network, a small addition to the knime.ini file may help: Help with the Extensions - #3 by marvin.kickuth