the "2180" refers to build number 2180 of service pack 2.. there are lots and lots of different build numbers for service pack 2 first you have to check which build number you are using (nLite is a good way to do this) then download the appropriate uxtheme.dll for that version sp1 is good because there is only one "final" sp1 version so everyone can use the same uxtheme.dll.... when sp2 goes official there will be only one "final" version of that also, but it's not out yet nLite very useful.. how else can you fit XP SP2, plus office 2003, plus photoshop cs, plus nero, powerdvd, acrobat, blah blah blah onto your cd?