Msgbox the values you are comparing.
It is a very good chance that Null math is tripping you off

This is also potentially rounding problem. The numbers you are seeing on the form rounded for display, but because of your calculations, the two numbers are not identical.
Display the numbers to four or even six decimal places

I did do a msgbox of the values. they are showing the same values 30.4, 30.4.

Try and wrap Each of  the numbers with the Round Function.

I did a display up to 5 decimal points.  It showing the same numbers, but still giving me the message that they are not equal

Where do I do a round,one number is coming from a form - is there a place I can specify it?

Did you Round them?

X = Round(value,2)

Y = Round(value1+value2+value3,2)

I am looking it up now on rounding

ah thanks, I will try it.

Brilliant.  Worked!  Thanks soooo much!

You're most welcome

This is due to floating point errors that are inherent to computer chips.  Sometimes even simple math can't be done.  Use the immediate window to calculate 0.1 + 0.2 - 0.3 and you'll be shocked to see it's not zero (see picture below).  This has been an issue since the dawn of computers right up to today.  It's not really the fault of Access.  Until new computer chips are invented to fix this, it will always be an issue in all software that uses floating point math.

Thanks for the additional insight, Kevin.