Hi,

I have around 8 input cells where the user can enter values. I have an 'error' cell that checks for an error condition (which involves all the parameters) and reads "Error" when true and "None" when false.

I have a userform with textboxes from where these input cells can be changed too. When a change is to be made, I store the last valid value in a variable and set the cell to the user specified value and check the status of the error cell. Incase it is true, I set the cell back to the original value else accept the current value.

The problem comes when the user enters values in the spreadsheet itself. I don't want the user to be able to enter values that lead to error. Is this possible to do (from the spreadsheet)? The data validation feature is not going to be to useful since the range is going to be dynamic. Any ideas?

Thanks for your time.

Regards,
Ram