Sorry, i just saw, that I had some problems with the braces:
(because of the word wrap i split up the formula, make sure
to put it back together in excel)

=IF(ISERROR(VLOOKUP(LEFT(B2,IF(
ISERROR(FIND(".",B2)),LEN(B2),FIND(".",B2)-1)),
C:C,1,FALSE)),"No Match", "Match")

hth

Carlo