How do I fix line 19? It says subscript out of range.

Why are IF on line 10 and ELSEIF on line 12 followed by same conditional expression?

*facepalm*

I fixed the conditional issue and added a value to the UNSHIFT line and it still gives the error.

Try to modify line 19 as follows. (before correction) CODE$[I]=PRGGET$() (after correction) CODE$[I-1]=PRGGET$()

Oh, thanks. I should re-learn arrays.

Something about prgedit and prgget$: PRGEDIT specifie a program and line to edit. The problem is that it start from line 0 and iterate until it reach the desired line. PRGGET$ read the current line and it move the pointer to the next line. If the file you're reading is too big, then you should remove prgedit from the "for" because the performance won't be good.