It sounds as if when the user enters the logon in A2, you want H2 to capture the time the entry was made.

This can be done be formula, but it can't be made to be static unless you use VBA.

The formula in H2 copied down would be =IF(A2<>"",NOW(),"")

but you have to place a time format on the cell on you will just get numbers.

The NOW() function in the formula is Volatile means if you select anything on the spreadsheet the time will change...it's dynamic.

You can test this by selecting F9 and you'll see the time change.

So, bottom line, if you want to lock in the time when A2 is updated, you'll need VBA.

Do you want to go this route?