1) The ASP ObjectContext and related utilities can be found installed in the IIS Utilities Application under COM+. Try installing your component that needs access to these in that same application right along with them.
2) Make sure that the user context that calls your component has permissions to actually launch it. What I do is go to Local Users and Groups, and set the password to the IUSER_machinename account to BLANK (no password). Then in COM+, right click on the Application (Package)your component is in and set the authentication to the IUSR account. Now any browser session should be able to run your component.
3) If all else fails, run DCOMcnfg and make sure your chosen user has launch and access permissions to your component.
Maxwell