Click the cell where you want to paste the formula. I encountered this problem too Excel 2013. On the Insert menu select Add-ins.
If a cell is blank the formula will assign the status open However if a cell contains a date then the formula will assign a status of closed The formula used is.
Select the cells you need to format as mac addresses. You can also click in the toolbar then choose New Formula. To paste the formula with its formatting on the Home tab click Paste or press V. When text in a cell is turned into a random formula.