Locking cells when today's date is passed.

Hello,
Thanks for you fast response.
I attached the sheet once more with two rows filled in it.
As you will see, there is a column named (Entry Date). This column run with a VBA code that generates the date automatically when all the corresponding columns are filled from (A5:M5). SO when the row 5 (For example) is filled with data, the code automatically generates with the entry date and remains the same even if the user closed and opened the sheet at any other date. Its not a "today()" function....
In that case, the entry date in rows 5 & 6 is 28/3/2014 because I entered the data today.
What I need to do is, when the user tries to edit those data after 28/3/2014, he receives an error message and the code prevents him from editing this data and at the same time the user has the option to write new data in other rows following those rows starting row 7.
I hope this is clear for you and I hope if you can respond to me with a code as soon as possible.
Thanks