Sorry to be a pain again, but i hope you can help with this, and thanks in
advance again.

I am trying the following

Cell A1 = Input time, i.e. 08:00:00
Cell B1 = Calcualte time, i.e. =A1+TIME(07,00,00)
Cell C1 = Input time, i.e. 06:00:00 (next day)
Cell D1 = Following statement
=IF(C1<(B1+TIME(12,00,00),"ERROR",C1+TIME(07,00,00 ))

The formula seems to work all right in the first instance, but assuming I
get the error message, and
go back and correct C1, the "ERROR" remains in D1.

Is there any way i can get the right time to display after correcting C1.

Thank you very much for your help it is really appreciated.

Regards