When using the pull-down entry function in Excel with the default settings, if you try to enter an item that is not in the list prepared for entry, an error message like the one shown below will appear and you will not be able to enter the item. In such a case, you can either allow any item to be entered, or display a message...

When using the sheet protection function, there is a function that allows detailed usage such as "allow selection and input in this range of cells, but not in other cells". For example, let's say you have a system that automatically creates transfer data when you enter a company name and amount of money as shown below. In this example...

If you are confused about reference relationships in Excel functions, you have come to the right place! This article details how to find references using trace arrows. In fact, you can easily visualize the relationship between cells from the formula tab. This article will help you understand complex functions.