Need help fixing a timesheet

[dcm262]

My manager is using Excel Microsoft Office 2010 as a time clock system to calculate the hours worked by entering the arrival and departure times for the employees. We are using this formula to calculate the hours worked, =IF(C1<B1,C1+1,C1)-B1 in DD HH:MM format where B1=clock-in time, C1=clock-out time, in H:MM:SS AM/PM format. However, the other day my manager overpaid one of the employees, and the total amount of hours after the deduction just shows as "####." My manager wants me to find a way where the "credit hours" show up in the worksheet so we can have it as a proof that we overpaid the employee. Is there a way to do that? If the amount of hours overpaid could only show up between parentheses as credit or with a negative sign, it would be great. Also, my manager would like to change the format for the hours worked from DD HH:MM format to HH:MM format. I tried to do a custom format for this, but after 24 hours the system does not add any other hour. I hope someone could help me with these two issues. Thank you in advance!

[ranman256]

Each clock time needs full date/time.

Mm/dd/yyyy hh:mm:ss

(Or whatever country format) but full date/time.