Lawrence,
You are going to need to post a code fragment of the line that's failing.
I created a form added array properties a through o and ran this code in the Load() and it worked perfectly:
debugout thisform.a[1]
debugout thisform.b[1]
debugout thisform.c[1]
debugout thisform.d[1]
debugout thisform.e[1]
debugout thisform.f[1]
debugout thisform.g[1]
debugout thisform.h[1]
debugout thisform.i[1]
debugout thisform.j[1]
debugout thisform.k[1]
debugout thisform.l[1]
debugout thisform.m[1]
debugout thisform.n[1]
debugout thisform.o[1]
>Yes