AMOS error - No list of input variables was found...

Hi All,

I am trying to calculate estimates in a relatively simple SEM with three latent variables and one observed variable. No groups at this stage. I uploaded the data file from SPSS and assigned each variable (in the diagram) a name based on the variables name in the SPSS data file. However, when I try to calculate the estimates, I keep receiving the following error message:

"No list of input variables was found.A list of input variables must appear once for each group."

Thank you for any ideas...