On Call Fridays can be a drag, but The Register has a formula to inject a little fun by delivering a new instalment of On Call – the reader-contributed column in which we share your tech support stories. This week, meet a reader we'll Regomize as "Albert" who told us about his time working for a substantial French consulting company's outpost in the north of England. "I was a software engineer working supporting various Oracle ERP integrations," Albert told On Call, before explaining that one integration saw data from Big Red's Payroll app piped into an Excel spreadsheet. The integration had worked for more than a year when an urgent support ticket landed in Albert's queue: The sheet's calculation of billable hours worked by employees had suddenly and mysteriously started producing inaccurate results that were off by around a third – a ratio he felt was somehow important. Albert opened the file provided by the user and quickly confirmed the sums were wrong.…