Highlight the return in the EFCenter, then instead of using Receive Acks, choose the Update Acks of Selected Returns and see if that pulls it in.

That did not work. There must be another way to find out why this happened.

How did you generate the form???? TIA

Form 100 is the CA state corporation return.  If you have ProSeries Professional and have CA State Corp product installed it should be available to you.

To Install the state Corp product  Update > Select and Download New Products.