Unable to upgrade the midserver for Quebec , we can see the below issue in the MID Server issues tab.
Unable to load key store, MID server will not able to function
keystore is corrupted
1. If the MID Server is running, go to the /agent directory and execute the stop script (.bat or .sh).
2. Delete the keystore directory.
3. Restart the MID Server using the start script (.bat or .sh).
4. On the instance, open the MID Server > Servers list.
5. Open the record for the restarted MID Server.
6. Select the Rekey UI which should take care of syncing the config file with the correct keystore sys_id
7. Select the Validate UI. The MID Server will clear the cache, restart, and regenerate the keystore. The MID Server record will report that it is Validated.