? Subscript indices must either be real positive integers

I encounted this error using version 4. I thought I was getting this error in version 3 b/c the variable n only appears as period (t+1), but the requirement that all variables show up in the current period as well has been dropped in version 4, so now I am not so sure. :confused: :confused:. Any ideas?

Thanks a lot. My code is attached.
RBC5_3.mod (3.99 KB)