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In the case of viewing Bills, since Bills are archived shortly after they're generated, when you choose the Bill Data you want to view, its data will nearly always come from the corresponding archive tables.
Go to Admin > Billing > Bill Generation, which will show you the Bills grid. When you select a bill and choose "View Bill" from the Grid Toolbar, the Bill view will open in a new tab as it always has. In the background, the system determines the Table locations of the bill data you selected, and displays it as usual.