Compare formula result to another cell

I have the attached workbook which contains a column with a date in, a column with a time in and a column which concatenates them into one. I have another column with a date & time in together and I want to compare the concatenated column with this one to highlight any differences.

I can get it to work if I do the concatenation formula then paste it values only and then press enter in the cell to convert the result to date and time but this won't be feasible for the amount of data I will need to do this on, any thoughts on how I can make this work just from the result of the concatenated formula?

Perfect thanks AliGW, I was using the & rather than the + and it wouldn't' work! so simple!