At random intervals, we experience an "The parameter '{0}' cannot be an
empty string. Parameter name: cookie.Domain" when attempting to view our
reports. We are running SQL Server 2008 Reporting Services in integrated
mode (with MOSS 2007). Our reports are deployed to a "Report Library" on
the same site as the pages that display our Reports. Reports are displayed
using the Report Viewer Web Part (the one that comes with SSRS for MOSS add
in). Each page has at most 4 reports being displayed at once. Our default
zone is FBA (via Windows LiveID). All reports are displayed from, and
deployed to, this zone. There is a second "NTLM" zone that is accessible
via the same host header, but different port. This hosting site is publicly
facing, but the area displaying reports only allows certain (FBA)
authenticated users access.

During troubleshooting, I setup an automated script that accesses my report
pages randomly. It seems that I get the error about once every 5 minutes
(assuming constant and random page requests). This leads me to believe its
some sort of session timeout or report request limit. I've checked all
report server config files and server settings and nothing is jumping out at
me.

I have found nothing out there that describes this issue or anything
remotely resembling it. Any/All comments, suggestions, tips, links, etc are
appreciated!

-Brian


P.S. - I logged this issued through "Priority Subscriber Support in MSDN
Forums", and there was no reporting services forum listed there. This forum
was the best option I could find for this issue. If it needs to be moved to
another forum, please just notify me.