I have run MANOVA with 3 groups in the independent variables and 8 variables for the dependent variables.

I have 4, 5, 5 subjects in each group respectively.

In the output, I get this message.

Box's Test of Equality of Covariance Matrices is not computed because there are fewer than two nonsingular cell covariance matrices.

I appreciate if someone can tell me what this means.

Thank you,