You might see the following messages in Minitab when using : 
 
- * ERROR * Number of corner points <= number of factors 
- * ERROR * Maximum number of corner points = 128 
The only factorial designs for which you can calculate power and sample size in Minitab are those that you can create using , with the exception of 2-level split-plot designs. 
 
For example, you can't calculate power and sample size for a design with 9 factors and 8 corner points (because it has more factors than runs) or a design with more than 128 corner points. 
 
For assistance in selecting an available factorial design, choose 
, select 
2-level factorial (default generators) or 
Plackett-Burman design and click 
Display Available Designs. This dialog box does not take any input, but displays a table that shows available factorial designs, based on: 
 
- the number of factors of interest 
- the number of runs you can do 
- the resolution of the design that you want 
You can only calculate power and sample size for designs that Minitab displays in these tables.