Why do i get a error 2465

[Reg Carnaby]

This works

Forms!frmLocotr olDE_Undetermin edGrid.[TextW(18)].Value = str(!CountOfwee k)

This gives the error

dim week as integer
....
week = 18
.....
Forms!frmLocotr olDE_Undetermin edGrid.[TextW(week)].Value = str(!CountOfwee k)

Have tried week as string, long, variant

Runing vb6.5 on vista