Thanks, Huw This is what I came up with in the end:function validrss(u,n)
dim objRss,strRss
validrss=true
if len(u)=0 or isnull(u) then
validrss=n
exit function
end if
if validlink(u,true) then
set objRss=server.createobject("Msxml2.ServerXMLHTTP.3.0")
objRss.open "GET",u,false
objRss.send
if objRss.status<>200 then
validrss=false
else
strRss=objRss.responsexml.xml
if instr(strRss,"<rdf:RDF")=0 or instr(strRss,"xmlns=""http://purl.org/rss/1.0/""")=0 then validrss=false
end if
set objRss=nothing
else
validrss=false
end if
end function