To update - the problem is now solved. The issue was that old SDSS metadata in the SP was still being loaded (though I thought I'd commented it out from the config) and the clash between it and UK Fed metadata meant that access worked (as far as we can tell) for IdPs which were in the SDSS federation before the UK Federation, and whose metadata had not changed in the meantime. Thanks to all those who helped test this and make suggestions. Cheers, Simon Jon Warbrick wrote: > On Fri, 16 Nov 2007, I wrote: > >> Simon McLeish of LSE and I are failing to get Cambridge's IdP to >> interwork with a Wiki at LSE, despite a number of other IdPs having >> no problem accessing it. [...] > > Many thanks to everyone who helped with this. > > Of 7 IdPs tested, 4 worked just fine, 2 failed with the same message > as mine, and one failed in a new and exciting way. Simon tracked the > problem to some stale metadata at the SP end which was confusing it > when dealing with IdPs like mine which are only in the UK Federation. > We still don't know why only some such IdPs were affected. > > Jon. > Please access the attached hyperlink for an important electronic communications disclaimer: http://www.lse.ac.uk/collections/secretariat/legal/disclaimer.htm