The sheet you selected is empty. Please select a different sheet.

I have a sheet with a count formula that references another sheet.  I have been able to set up values to many cells already, then suddenly I started getting the error that the sheet I am trying to select is empty.  I had deleted a "test" row, but even if I put information back in there, it won't allow me to select the new sheet to reference.  Any ideas on how I messed it up?

Thanks,

J