Question:

As default, users will land on the Home tab once logging into Vault, but why does the user always land with the error "Page Not Found"?

Answer:

The URL of the "Page Not Found" page contains `t/0TB000000000K15`, which is the URL to a tab.

So it is possible that the tab is no longer available, and there could be two reasons:

1. The landing tab of the user was specified, and the landing tab no longer exists in the system.
2. The user logs in by clicking a bookmark saved locally which refers to a tab URL that is no longer available.

Related Documentation:

Vault Help: How to Set the User Landing Tab