You're welcome to the link.
It seems that the terms of the WMD inspection regime were faulty; requiring a full accounting of every little nut, bolt and washer, which in the aftermath of the 1st Gulf War was impossible.
What could be accounted for was accounted for but some things had 'disappeared', been destroyed by US bombing, looted, lost, destroyed by the Iraqi's, whatever and the full accounting required by the UNSCOM charter was impossible.
What the UNSCOM inspectors knew and repeated loud and clear and often was that Iraq no longer had a WMD production capability and had not had such since the 1991 war.
CIA, MI6 and the BND (along with UNSCOM) knew of Iraq's incapability to produce WMDs even as Bush et al were touting the certainty.