PostGreSQL service is needed for allowing logins with the WebUI. If the service is not running, logins to the Web UI won't happen.
If you notice the service is stopped, quickest thing to do would be to start the service. If there are deeper problems, the service may not start.
First step would be to check the windows system events for more information on the problem. It may not always have complete information on the problem.
If the Windows System events don't show anything. you can look in the PostGreSQL logs located in the \PrognosisData\PostgresData\log folder. (or C:\PrognosisData\PostgresData\pg_log depending on version)
Check the most recent file for errors. You may see errors regarding primary check point record.
"could not locate a valid checkpoint record "
“PANIC: could not locate a valid checkpoint record
This error could indicate that there is some corruption in the Postgres Transaction log. To fix this, you will have to reset the the transaction log with the "pg_resettxlog" command from the command line. At first, You may get a permission denied error
To get past that error, you will have to delete or rename the transaction log file. To do this, browse to the \PrognosisData\PostGresData\pg_log folder for older prognosis versions or the C:\PrognosisData\PostgresData\pg_xact folder for newer or current version.
After that, you can try run the pg_resetxlog command and it should run.
And a new TX log is created.
After that you can start the Postgres service and log on to the web UI.
