|First off, I'm not sure why "programming" would force you to rename the sheets. You can refer to a sheet in VBA without caring (or even knowing) what it says on the tab.|
Let's says Sheet1 has been named One and Sheet2 has been named Two.
In VBA you can refer to these sheets as Sheets("One") and Sheets("Two") or as Sheets(1) and Sheets(2) where the 1 and 2 depict the order of the sheets in the workbook. If you refer to the sheets by number, you shouldn't have to care what it says on the Tab.
That said, if you really want to rename the sheets back their original names, use this code. It refers to each sheet by it's number and uses the same variable to build the sheet name.
For Sht = 1 To Sheets.Count
Sheets(Sht).Name = "Sheet" & Sht