Existing web content has a report with drill through's to another report.
I made a change to the drill through target report, so that it now requires additional parameters. I also made changes so that the drilling report passes them.
However, when I click the link to drill through, my report viewer vanishes. I haven't been able to find an actual error or exception, however.
My gut tells me its a simple mistake, but since I cannot seem to find an actual error happening at this point, I'm not sure. The drill through event in the code behind seems to execute w/o issue, and is unchanged from the previous working version.
Is there a particular class of problem that results in this sort of behavior.. no error, but the report viewer vanishes?
Anyways, at this point, the web application looks OK (minus the missing report viewer) but is in a broken state, where whatever I do next results in an error, and whatever I do next, I get this error (which I suspect is only a side effect, and not a root cause of my problem.)
Message : Failed to load viewstate. The control tree into which viewstate is being loaded must match the control tree that was used to save viewstate during the previous request. For example, when adding controls dynamically, the controls added during a post-back must match the type and position of the controls added during the initial request.