Shibboleth SP3 Problem: xmltooling::IOException setHeader (Header) failed: -2147024809

[Cantor, Scott]

That's an E_INVALIDARG code, and I have never heard of it happening, those error checks are practically cosmetic. My guess is the attribute data that was decoded and eventually passed through is unusual in some way if it's reproducible.

The only parameters are the header name, which is obvious fixed, the data, and the length. That doesn't leave much to be invalid. 

-- Scott