There was this one time when I was working on a project and we were trying to load a datawarehouse. I came in one morning to find a team member staring at a failed SSIS package with this error message at a Data Flow Task, specifically coming from the query in the ole db source:
[SRC_OLEDB ] Error: SSIS Error Code DTS_E_OLEDBERROR. An OLE DB error has occurred. Error code: 0x80004005.
An OLE DB record is available. Source: “Microsoft SQL Server Native Client 10.0” Hresult: 0x80004005 Description: “Internal Query Processor Error: The query processor encountered an unexpected error during execution.”.