That's not a database error, it's an error from the application. I'd guess that the application lost connection for some reason (cluster failover will do that, as will many network problems)
Speak to the application developers or if it's a vendor app to the vendor support and find out exactly what causes that error.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability
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