I have an XT, and a 550EX flash. The focus assist light, however, will not come on in "P" mode or any other creative zone mode. In Green mode, however, the flash assist light works.
I have checked the custom functions and made sure the "external flash emits" option is selected. Still didn't work. I cleared all the custom functions. Still doesn't work. I reset all camera defaults. Still doesn't work.
Any ideas what may be the issue? If I am trying to take a flash picture in dim light, I obviously want the flash assist beam to activate. Thanks!