I'm trying to format cells in Excel so that they display the total duration of phone calls as
hh:mm:ss, but Excel is giving me errors.
Sometimes durations are only
mm:ss (49:10), or even just
ss (35), and I need them by default to change to
00:00:35 respectivly. However, when I select 'Custom' on the 'Number' tab when formatting the cells and enter either
##:##:##, Excel tells me -
Microsoft Office Excel cannot use the number format you typed.
hh:mm:ss will not work for me, as I'm dealing in durations, not times. Is anyone able to tell me how do format this? Thanks.