COMException "Unexpected error." on InfoStore.Query()

I've inherited an ASP.NET 2.0 application that essentially provides a limited portal to our (hundreds of) Crystal reports.  I've been tasked with upgrading as many of the technologies as I can to more current versions, including the .NET framework.  We're targeting .NET 4.0, because other systems on our Crystal server can't handle 4.5 yet.

I'm not sure what iterations our Crystal server has gone through, but currently we're running BI Platform 4, Feature Pack 7.

My ASP.NET application (coded in VS2012 Pro update 4) can use either AD or Enterprise authentication and successfully log onto the server.  (I can tell because it throws an exception if I pass incorrect credentials.)  However, when I attempt an InfoStore.Query(), it throws a COMException with the message "Unexpected error.", no inner exception, HResult of 0x8000FFFF.

The query itself works fine in the query tool.  Here's the relevant code:

using CrystalEnterpriseLib;

using CrystalInfoStoreLib;

        public InfoObjects GetCrystalReportFolders()

        {

            EnterpriseSession es;

            SessionMgr sm = new SessionMgr();

            es = sm.Logon("", "", "servername", "secWinAD");

            InfoStore iSt = new InfoStore(es.get_Service("InfoStore", "servername"));

            return iSt.Query(

                @"SELECT SI_NAME, SI_ID, SI_PROGID, SI_PARENTID  FROM CI_INFOOBJECTS

                    WHERE (SI_PROGID = 'CrystalEnterprise.Folder'

                    or (SI_PROGID='CrystalEnterprise.FavoritesFolder' AND SI_Name='username'))

                    AND SI_INSTANCE=0 Order by SI_NAME");

        }

Couple questions:
1. Does BI 4 fp 7 support ASP.NET 4.0 and VS2012?

2. Any hints as to what else I should check?

Thanks.

John