I tried moving my web application from the development to production server.
Development is running Windows 2000 Advanced Server, production is running
Windows Server 2003.  This is what I did to install it (on both Dev and
Prod; the steps were identical):
   Moved COM objects to server
   Added COM objects to GAC
   Used regsvcs to register all objects from the GAC into COM+
(forty-something objects grouped into a half dozen or so applications)
   Created a local user account on the server
   Set each COM+ application to run with the Identity of that user (not
"Interactive User")
   Copied the compiled web pages (including /bin folder) to the server
   Configured a new IIS web site, pointed to that folder

On both machines, I can hit the web site and it brings up the login page
fine (which is currently a very simple page that makes no object calls).
When I log in, it makes a call to one of my COM objects (which then calls
others).  On Dev (the Win2k box), it runs fine, but on Prod (the Win2k3
box), I get the error included below (with a couple lines about "this was an
unhandled exception" removed to make it a bit more brief).  If I make the
COM+ user a member of the machine's Administrators group, it runs fine, but
that kind of defeats my intent of creating a new user.  I'm registering the
objects manually (using another, Administrators-group-member user) rather
than using "automatic" or "lazy" registering, so that shouldn't be my issue.
And it works as-is in Win2k.  What do I need to do to get Win2k3 to allow
it?

Server Error in '/' Application.
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Exception Details: System.Runtime.InteropServices.COMException: Exception
from HRESULT: 0x80131700.

Stack Trace:

[COMException (0x80131700): Exception from HRESULT: 0x80131700.]
  System.Runtime.InteropServices.Marshal.ThrowExceptionForHR(Int32
errorCode, IntPtr errorInfo) +0
  System.EnterpriseServices.Thunk.Proxy.CoCreateObject(Type serverType,
Boolean bQuerySCInfo, Boolean& bIsAnotherProcess, String& uri) +581

System.EnterpriseServices.ServicedComponentProxyAttribute.CreateInstance(
   Type serverType) +181

System.Runtime.Remoting.Activation.ActivationServices.IsCurrentContextOK(
   Type serverType, Object[] props, Boolean bNewObj) +74
  MyWeb.LogOn.btSubmit_Click(Object sender, EventArgs e) in
c:\inetpub\wwwroot\MyWeb\LogOn.aspx.vb:48
  System.Web.UI.WebControls.Button.OnClick(EventArgs e) +108

System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.
   RaisePostBackEvent(String eventArgument) +57
  System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler
sourceControl, String eventArgument) +18
  System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +33
  System.Web.UI.Page.ProcessRequestMain() +1277

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Version Information: Microsoft .NET Framework Version:1.1.4322.573; ASP.NET
Version:1.1.4322.573