ImageVault Core service not working due to mismatch with database schema and code versions

Just as a note to self. We recently did a POC on upgrading to the latest EPiServer (8.5 to 9.5) and ImageVault (4.X to 4.8) versions for my current client’s website. Everything went as expected, there were a few things that wouldn’t build in Visual Studio which were easily fixed. After switching back to do work in another Git branch I returned to the POC code a few days later.

Error when accessing ImageVault's UI in EPiServer

ImageVault’s UI in EPiServer was not behaving, even though it had done so right after the upgrade. Looking through the log files generated by the ImageVault Core service helped with concluding what was wrong.

System.Data.EntityCommandExecutionException: An error occurred while executing the command definition. ---> System.Data.SqlClient.SqlException: Invalid column name 'ApplicationName'.
Invalid column name 'Author'.
Invalid column name 'RedirectUrl'.

There was a mismatch between the upgraded ImageVault Core source code and the database currently restored in place of the upgraded one. Running the installation process again through EPiServer’s Deployment Center upgraded the database schema and fixed the issue.