Excel crash as the result of file look-up
 

The code I wrote here looks up the content of B3 in the specified table
and looks up the corresponding value to B3 in the table.

=IF($B3="","",VLOOKUP($B3,'\\location\[Filename.xls]SheetName'!$E$40:$BN$1917,P$1,FALSE))

But it one day stopped updating the values, and now when I manually
step into the code and press [Enter] the Excel asks for the file to be
located, and upon my browing through the folders and selecting it,
Excel just crashes. The most mysterious problem...any solutions?

Cheers