OK. I created a command for the active LoginID's. Created it with the database expert. Found an SQL expert to help me, and we coded this new command to include only LoginID's that also had an email address. This command is used by my active loginid parameter as a dynamic prompt.
After this I have three files connected in my reports's database expert, the header file, a detail file, and a command file. The detail and command are connected to the header with left outer joins.
At this point it works great.

I then add a second command for the inactive LoginID's, LoginID's that lack an email address. Connect this command to the Header file with a left outer join. This command is used by my inactive loginid parameter as a dynamic prompt. Run the report and everything works just fine...
Make the report available to users and they get the following error:
Prompting failed with the following eror message: ''.
Error source: Error code: 0x80070057
Any clues?