The values for horizontal and vertical grid spacing must be positive integers greater than zero.

In the Tools Options for the HTML Designer Display, you have entered values in the Horizontal Spacing or Vertical Spacing fields that are not positive integers greater than zero.

To correct this error

1. From the Tools menu select Options, and under HTML Designer select Display.
2. Enter values in the Horizontal Spacing and Vertical Spacing fields that are positive integers greater than zero.