VLOOKUP

[Nena]

When I try to run this macro I pop box says, "Excel cannot complete
this task with available resources. Choose less data". What am I
doing
wrong?

ActiveCell.FormulaR1C1 = "=IF(ISNA(VLOOKUP(RC[-5],'Fall 2006 Cohort'!
R2C1:R65536C28,13,FALSE)=TRUE),"""", VLOOKUP(RC[-5],'Fall 2006
Cohort'!
R2C1:R65536C28,13,FALSE))"
ActiveCell.Offset(0, 1).Select


Thanks in advance.