Excel macro
 

I am changing a cells formula when user selects a number. The macro sets the
formula for the cells. These 2 formulas are identical but Excel keeps
inserting a '\' before the \HOP when they are entered. Both files exist in
the same directory and both references are vaild. I am trying to avoid using
Network drive letter so that users may copy onto local machine

This one does not, Excel forces the extra \ before "\HOP". Even if I delete
the extra \ and hit enter Excel forces it back in.

=VLOOKUP($B$3,'\\Techfil01v06\Ris\TSS\\HOP\TL
Summary\HOPGroupSummP1206.xls'!GroupSummary,9,0)

This one works fine because Excel is not forcing the extra \
=VLOOKUP($B$3,'\\Techfil01v06\Ris\TSS\HOP\TL
Summary\HOPGroupSummP1106.xls'!GroupSummary,9,0)

Can someone explain?