How to parse to columns of data and have excel list the differences in each column?

Sorry for the really long title. I am not quite framing that correctly. Let me try to explain

I have to lists of servers from two different input sources. One for Vantive and one from our main data collection server. I have made two columns, one from Vantive and one from DAPC11 (our main server) Vantive lists 1677 servers in our environment. While Dapc11 only registers 1559 servers in the environment. I have placed each column of servers in Column A and the other in Column C.

My Goal............

To have Excel parse both columns of data, sifting through both and finding which servers are not found in the two lists. I will try and show a crude example below.........

PHP Code: 

Column A                                          Column C 
TGT1KKA                                           TGT1KKA
TGT1KKB                                           TGT2KKC
TGT2KKC                                           TGT2KKD
TGT2KKD                                           DFCHRA
DFCIEH                                            DFCIEH 


As you can see Column C is missing TGT1KKB and has DFCHRA extra in its column as compared to Column A. Column A is missing DFCHRA.

I am wanting to have Excel parse these two columns of data, finding like examples in both and disregarding them. And only reporting irregularities between the two. Excel could go as far as saying in Column you are lacking these servers or you have this many extra servers, and list them out either way. The same would go for tallying up Column C in the same fashion.

I sure hope I am trying to say or type this correctly. Thank you in advance for baring with my crazy thoughts, but its something for work I want to get accomplished.

Many thanks for any input or ideas in advance!

Regards,

James
St. Louis MO

in col b something like
=if(countif(c:c,a1),"in col c","not in column c")
and likewise in col d
=if(countif(a:a,c1),"in col a","not in column a")
ther are several diferent ways of doing this