I am trying to combine a date/time reference (B10) with another column (C10)
containing milliseconds. I would like to display the date/time and the
milliseconds in another column (D10) like dd/mm/yyyy hh:mm:ss.000.

I have tried the following, but none seems to work:
=DATEVALUE(B10)+TIMEVALUE(B10)+TIME(0,0,C10)
=B10+TIME(0,0,C10)

Both formulas result appears the same as the reference time in B10 even
after selecting the custom format of dd/mm/yyyy hh:mm:ss.000.

Appreciate a suggestion.

Thanks,
Bruce