.STH File

The sth file extension is related to Lotus Domino, an enterprise level application platform from IBM.

A typical sth file contains securely stored password for a Lotus Domino keyring (KYR format).

These files are created whenever a new server key is generated.

Files with sth file extension can be found as so call password stashes from the Lotus Domino platform by IBM. Contains securely saved passwords.

How to open:

These files are not meant to be opened directly.

How to convert:

A conversion of any kind, for this type of *.sth files seems to be highly unlikely.