1. If the dates in your example are in A1:A7, and the times in B1:B7, enter the formula in my prior post in C1 and copy down to C7.

2. Copy C1:C7, then do Edit > Paste Special > Values.

3. Copy C1:C7 again, select A1, and do Edit > Paste Special > Add.

4. Format A1:A7 as dd/mm/yyyy hh:mm (or whatever date and time format you wish), and delete columns B and C. The dates and times are now in column A.