VBA script error help: Run-time error'9': Subscript out of range.

Hi Pros!
i'm newer in VBA.When i wanna open a file excel that's name "HNI_ROUTE_HO SO.xlsx" by code like this:

Sub ActiveWorkBook()

    Application.Workbooks("HNI_ROUTE_HO SO.xlsx").Activate
End Sub

It didn't work and have warning: Run-time error'9': Subscript out of range.
Plesase explain for me this problem.
Thanks!

Welcome to the forum!

I suspect, from this opening post, that you have not read our forum rules. Please do so now (link at the top).

I have added code tags for you this time - please do so yourself in future (instructions in the forum rules).

Your title is not acceptable - I will change it for you this time to show you what we expect of you in future.

Thanks.

Hi, welcome.
Do you mean this?

Sub dotch()
    Workbooks.Open ("HNI_ROUTE_HO SO.xlsx")
End Sub