Internal Server Error, 500

Causes

After publish you get an error like this

Internal Server Error, 500: Publish or checkout issue,

Or you get a lot of files with “Checkin Error” status

In that case your database is full, it is generally due to SQL Server Express usage

This is usually due to the use of a SQL Server Express database which is limited to a size of 10GB

Solution

Migrate to a SQL Server database edition other than SQL Server Express
https://sqlserverbuilds.blogspot.com/2019/02/sql-server-editions.html