I came across an error and I though this might happen to some folks in the future, so thought I'd scribble it down here.
K2 server throws the following error when trying to start new process instances: "A database error occurred". And in the K2Error.txt it was logged as "K2Sql.LoadProcess: Object reference not set to an instance of an object.".
The problem in my case was that the Process files referenced assemblies that were in the GAC on the Dev machine, but were exported to a Test machine where these assemblies were not in the GAC. So the Test machine hit these exceptions. The problem was solved when these assemblies were added to the GAC on the Test machine.
Error: "A database error occurred"
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