Edit sub DoHideCategory so it now reads:
Sub DoHideCategory(intCatId)
HideForumCat = strUniqueID & "HideCat" & intCatId
if Request.QueryString(HideForumCat) = "N" then
Response.Cookies(HideForumCat) = "N"
else
Response.Cookies(HideForumCat) = "Y"
end if
Response.Cookies(HideForumCat).Expires = dateAdd("d", 30, strForumTimeAdjust)
end sub