The modpack manifest could not be fetched
What it looks like in your log
Failed to download modpack manifest
What causes it
The installer could not retrieve the pack definition: a wrong pack id or URL, a deleted pack version, or blocked outbound network.
How to fix it
Pin a pack version that still exists, check the URL or id, and confirm the machine can reach the pack host.
Not sure this is your problem? Paste your log and Roastd will tell you which of these it actually matched, and what else it found.
Check your own log