VBA : Lock column after data entry

I tried to play around it with again, the moment you type in anything in the D column the sheet becomes locked.

You have to make sure that all the cells in the range where you will be entering data (Range("A3:D23") in your sample file) are unlocked before you run the macro. If you are still having problems, please post a copy of your actual file. It is always easier to help if we can work with the actual file. If the file contains confidential information, replace it with generic data.