"Aladin Akyurek" wrote...
....
If an item ID is not in ...!$A:$A, you'll fetch a wrong value, in case
the value in ...!$A:$A is lexically or otherwise smaller than A5 is not
admissible. The remedy would be:

=IF(LOOKUP($A5,x!$A:$A)=$A5,LOOKUP($A5,x!$A:$A,x! $K:$K)

Substitute
'M:\Finished_Goods_Kanbans\[PullItemStatus.xls]PullItemStatus' for x,
which I used as an abbreviation.

This won't necessarily help. The pathname to the left of the filename is the
key. It means the workbook isn't necessarily open. When it's not open, *ALL*
external references into it resolve to *ARRAYS*, **NOT** ranges. Arrays
can't span 65,536 rows, but ..!$A:$A and ..!$K:$K would do so. That this is
an intermitent problem for the OP is likely due to this other workbook being
open sometimes and closed other times.

If this workbook won't necessarily be open, don't use entire column
references. Use $A$1:$A$65535 and similarly for col K.