Something to investigate/verify...
Forget when/where some of these settings came into effect; Win7 is a bit dusty in the grey matter.
Does Windows allows (admin) accounts to have blank password; if not, need to do a REG entry or maybe a GPO setting
Account CAMERAS can be logged (kb/monitor) into without using a password; yes i know, but have to ask it
Account CAMERAS has the right/privilege to start a service
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BI prompt is collecting USER and PASSWORD to set these values within the BI Service.
.\BIservice would be seen as .\Cameras on your system
For password and confirm password blank-out field and enter nothing
You may be able to enter anything you want (sic garbage) at the BI prompts, then manually edit these yourself from within Services (CMD prompt> services.msc)