On second look it seems to me there is a \ missing from the filename:
='C:\extrafiles\SecondaryLevel[BofACheckRegister.xls]Payable'!CurrentBa
l

I would expect it to be:

='C:\extrafiles\SecondaryLevel\[BofACheckRegister.xls]Payable'!CurrentB
al

However, when I try to reproduce the problem by removing the "\" from a
valid link I get a #REF error rather than #NAME. The only way I get
#NAME is if I use a range name that is not present in the referenced
worksheet.

Why not start again, Edit Copy the cell you want to link to and Edit
Paste Special Paste Link into the cell containing the formula that
is not working.

Bill Manville
MVP - Microsoft Excel, Oxford, England
No email replies please - respond to newsgroup